Siri Vangen

• Mentzoni, Camilla Tjønneland; Røe, Kjerstine; Bjellmo, Solveig; Carlsen, Marte Irene Skille; Christiansen, Marit Halonen & Fjeldstad, Tora Sandvik [Show all 15 contributors for this article] (2026). Learning opportunities in eclampsia care: A ten‐year audit from Norway, 2013–2022. Acta Obstetricia et Gynecologica Scandinavica. ISSN 0001-6349. 105, p. 1767–1777. doi: 10.1111/aogs.70280. Full text in Research Archive Show summary

  Introduction The World Health Organization recommends surveillance, including audits with case reviews of severe maternal morbidities such as eclampsia, to improve obstetric outcomes. We aimed to audit eclampsia and to identify learning opportunities in eclampsia care in Norway. Material and Methods Our study population included all women discharged with a diagnosis of eclampsia (ICD‐10: O15) and with a documented generalized seizure in medical records at two university hospitals in Norway from 2013 to 2022. An eclampsia working group developed a digital eclampsia case report form for gathering clinical information from medical records. Based on a structured summary of information from the digital case report form, the group reviewed the care for women with eclampsia. Each case was discussed and reviewed according to the clinical guidelines by the group. Learning opportunities to improve care were identified and classified according to whether they contributed to the outcome. Results Among 93 139 deliveries, 22 women with an initial eclampsia diagnosis were identified (2.4 per 10 000). Subsequent clinical information identified an alternative probable etiology of seizures in five women. None of the 22 women received magnesium sulfate prior to the seizure, and cerebral imaging was performed in 11 of 22 women. In 18 women, learning opportunities were identified, and for eight women, a different management could potentially have prevented eclampsia. The eclampsia working group identified learning opportunities related to underuse of magnesium sulfate prophylaxis when indicated, inadequate management of hypertension both before and after eclamptic seizure, underuse of cerebral imaging as a diagnostic tool, and lack of follow‐up consultation with an obstetrician in women diagnosed with eclampsia. Conclusions Learning opportunities were found in 18 of 22 women, and improvements in care could potentially have changed the outcome for eight of the women. This audit highlights the importance of differential diagnostic consideration for seizures in pregnant and postpartum women, the use of prophylactic magnesium sulfate when indicated, and the diagnosis and management of hypertension in pregnancy. Eclampsia audits should be incorporated into national routine surveillance and learning systems to improve obstetric care.

• Topranin, Virginia de Martin; Brørs, Gunhild; Sæther, Julie Caroline; Gerdts, Eva; Vangen, Siri & Bye, Anja (2026). Translation and validation of the Norwegian ABCD Risk Questionnaire to assess cardiovascular disease knowledge and risk perception prior to myocardial infarction. BMJ Open. 16(6). doi: 10.1136/bmjopen-2026-118713. Full text in Research Archive Show summary

  Objectives: The aim of this study was to translate the Attitudes and Beliefs about Cardiovascular Disease (ABCD) Risk Questionnaire into Norwegian and assess its psychometric properties among individuals with a history of myocardial infarction. Design: The study adopted a cross-sectional design. The original questionnaire was translated into Norwegian and adapted for use in the target population. The Norwegian version was pilot tested in a sample of patients and then validated in the target population. Setting: Norway, using a web-based solution to collect data. Patients: A random sample of Norwegian individuals <85 years old with a history of myocardial infarction and no cardiovascular disease before their first myocardial infarction. Main outcome measures: Internal consistency was tested using Cronbach’s α and test–retest reliability using intraclass correlation coefficient (ICC). Difficulty and discrimination indices were determined for the Knowledge scale. Confirmatory factor analysis (CFA) was used to assess structural validity of the Risk scale. Results: Data for 746 participants (mean age, SD: 66.4, 10.3 years), of which 26.9% females were analysed. The Norwegian version showed satisfactory internal consistency (Cronbach’s α 0.73–0.79) but modest test–retest reliability (ICC 0.35–0.64). The Knowledge scale showed moderate difficulty (0.39–0.84) and good discrimination power (0.44–0.60). The one-factor model CFA for each scale achieved acceptable fit, and the four-factor model showed moderate fit (root mean square error of approximation=0.05, standardised root mean squared residual=0.07, Comparative Fit Index=0.91, Tucker-Lewis Index=0.88). Conclusions: The Norwegian translated ABCD Risk Questionnaire demonstrated satisfactory psychometric properties and can be considered a useful instrument for assessing knowledge and risk perception among individuals with a history of myocardial infarction.

• Natvik, Marianne; Brekke, Mette; Vangen, Siri & Skjeie, Holgeir (2026). Finding sense of coherence in the menopause transition - A qualitative interview study with menopausal women in Norway. Women's Health. ISSN 1745-5057. 22. doi: https:/journals.sagepub.com/doi/10.1177/17455057261459816. Full text in Research Archive Show summary

  Background Women express lack of knowledge about the menopause transition, finding it hard to understand and navigate symptoms. This period may negatively influence quality of life and level of functioning. Objectives To explore menopausal women’s experiences, perspectives and coping strategies to comprehend, manage and find meaning in the menopausal transition. Design Individual interviews of women with different backgrounds and menopausal experiences, recruited by hairdressers in Norway. Methods Semi-structured in-depth interviews were conducted with 11 women in 2024. Data were analysed using reflexive thematic analysis. The theory of Salutogenesis and Sense of Coherence developed by Antonovsky, was used as guiding theoretical lens. Results Three main themes were developed, incorporating the intercorrelated aspects of Sense of Coherence : Comprehensibility, Manageability and Meaningfulness. 1. A transition from the unknown to normalisation – without knowledge, understanding menopausal changes was challenged, but normalisation of menopause gave comprehension. 2. From distress and silence to empowerment – manageability increased with comprehension, discussions with other women and knowledge dissemination, but was challenged by inadequate health care. 3. Finding meaning in the change menopause brings – meaningfulness motivated to seek understanding and coping strategies, and gave acceptance and value to this transition, although often accompanied by an undesirable sense of aging. Conclusions This study shows the importance of enhancing knowledge among women, the public and general practitioners to understand and manage menopause, and to improve menopausal care and women’s quality of life.

• Stalheim, Astrid Melteig; Nilsen, Roy Miodini; Vangen, Siri; Vik, Eline Skirnisdottir; Alnæs-Katjavivi, Patji Haakon & Iversen, Marjolein M. [Show all 8 contributors for this article] (2026). Adverse pregnancy outcomes in women with type 1 diabetes: A nationwide, population-based study, 1999–2021. Acta Obstetricia et Gynecologica Scandinavica. ISSN 0001-6349. p. 1–13. doi: 10.1111/aogs.70215. Full text in Research Archive Show summary

  Introduction For the total population and for groups of non-immigrant and immigrant women, we examined the associations of maternal type 1 diabetes with adverse pregnancy outcomes among women who gave birth in Norway from 1999 to 2021. Further, we examined the associations between the two time periods 1999–2014 and 2015–2021 and adverse pregnancy outcomes, and whether these associations differed in women with or without type 1 diabetes. Material and Methods In this nationwide population-based observational study, with data from the Medical Birth Registry of Norway and Statistics Norway 1999–2021, we used logistic regression to examine the associations between type 1 diabetes and adverse pregnancy outcomes. Moreover, differences in ORs for adverse pregnancy outcomes between those with and without type 1 diabetes were compared for the two time periods 1999–2014 and 2015–2021 using interaction analyses. Analyses were performed for the overall population, as well as separately for non-immigrant (n = 964 542) and immigrant women (n = 257 409). Results Women with type 1 diabetes (non-immigrant women n = 5067 and immigrant women n = 619) had higher ORs for almost all adverse pregnancy outcomes (OR 1.41–11.04) compared to women without diabetes in the period 1999–2021. In the time period 2015–2021, compared to 1999–2014, women with type 1 diabetes had a notably reduced OR of congenital malformations compared to those without diabetes (p interaction: 0.006). Immigrant women with type 1 diabetes had a higher OR in 2015–2021 vs. 1999–2014 of having large for gestational age infants (p interaction: 0.003). Conclusions Women with type 1 diabetes had higher odds of most of the examined adverse pregnancy outcomes, though improvements were observed from 2015 to 2021 compared to 1999–2014, particularly a reduction in congenital malformations. In contrast, immigrants had higher odds of large for gestational age. These findings highlight the continued need for targeted interventions to reduce the burden of adverse outcomes in all women with type 1 diabetes.

• Nordklev, Cecilie Bryn; Costa, Denise Reis; Nilsen, Roy Miodini; Morken, Nils-Halvdan; Vangen, Siri & Sitras, Vasilis (2026). Impact of National Screening Programs on Down syndrome prevalence and outcomes. Acta Obstetricia et Gynecologica Scandinavica. ISSN 0001-6349. 105(4), p. 613–620. doi: 10.1111/aogs.70157. Full text in Research Archive Show summary

  Introduction: Over the past five decades, antenatal screening programs have evolved significantly, primarily through advancements in ultrasound technology and the shift from invasive to non-invasive prenatal testing methods. This study aimed to evaluate the impact of these developments in prenatal screening for Down syndrome (DS) on the prevalence of live and stillbirths, as well as terminations of pregnancy (TOP) with DS. Material and Methods: This population-based registry study included all pregnancies in Norway from 1967 to 2021, with data on TOPs available from 1999. Information on DS pregnancies was obtained from the Medical Birth Registry of Norway. Logistic regression models were applied to evaluate time trends and maternal characteristics associated with TOP. Results: Among 3 231 159 pregnancies, 4764 (0.147%) were affected by DS. The prevalence of DS pregnancies increased from 0.165% in 1999 to 0.251% in 2021. During this period, the proportion of TOP rose from 20% to 55%, while prenatal detection rates improved from 18% to 70%. Despite increased detection, the proportion of TOP following prenatal diagnosis remained stable at approximately 80%. The prevalence of live births with DS remained stable at approximately 0.106%, while the prevalence of stillbirths was around 0.008%. Maternal age, parity, country of birth, and region of residence were associated with TOP decisions. Mean gestational age at termination decreased from 17.5 to 15.7 weeks. Conclusions: Over recent decades, prenatal detection and termination of DS pregnancies have increased. However, the proportion of women continuing pregnancies after a prenatal diagnosis and the prevalence of live- and stillbirths with DS have remained stable.

• Kvalvik, Sedina Atic; Åmark, Hanna; Helmig, Rikke Bek; Gissler, Mika; Nyfløt, Lill Trine & Skrede, Steinar [Show all 9 contributors for this article] (2025). Maternal deaths from sepsis in the Nordic countries during 2005–2021: A descriptive study. Acta Obstetricia et Gynecologica Scandinavica. ISSN 0001-6349. 104(9), p. 1783–1792. doi: 10.1111/aogs.70011. Full text in Research Archive Show summary

  Introduction: Maternal sepsis is a heterogenous condition which can arise from several different infections during and after pregnancy. Common for all etiologies is a high mortality rate. In a global perspective, maternal sepsis is an important contributor to maternal death. This study aimed to evaluate the clinical management of maternal deaths from sepsis in the Nordic countries and identify areas for improved clinical handling. Material and Methods: We used data from the Nordic Maternal Mortality Collaboration including maternal deaths from the five Nordic countries from 2005 till 2021, identified through linked registers. The national audit groups assessed each maternal death based on hospital records and classified it according to cause and quality of management. We formulated learning points to improve future clinical care in cases of maternal sepsis. Results: In total, 267 maternal deaths were identified, equaling a maternal mortality rate of 5.9 per 100 000 live births (95% CI 5.25–6.62). Maternal sepsis accounted for 9.7% of the maternal deaths (n = 26), ranking sepsis the fifth leading cause. Nongenital sepsis and genital tract sepsis numbers were almost equal. Substandard care was identified in 57% of cases with nongenital infections, and in 83% of genital tract sepsis cases. Improvements in care that possibly could have influenced the outcome were noted in 29% and 67% of cases, respectively. In nongenital sepsis, delayed recognition of sepsis and delayed administration of antimicrobial therapy were the commonest elements in substandard care. Delayed recognition of sepsis, delayed administration of antimicrobial therapy, and postponed or lacking surgical source control were the main elements in substandard care of genital tract sepsis. Conclusions: In the Nordic countries, sepsis was the fifth leading cause of maternal deaths during 2005–2021. In one-third of maternal deaths from nongenital sepsis and two-thirds of maternal deaths from genital tract sepsis, clinical measures could have reduced the risk of fatal outcome, emphasizing the need for maximal awareness and improved clinical handling.

• Andreassen, Silje Malen; Costa, Denise Reis; Laine, Hely Katariina; Evenson, Kelly R.; Vangen, Siri & Owe, Katrine Mari (2025). Registered report: Predictors and trajectories of physical activity before, during, and following twin pregnancy from the Norwegian Mother, Father and Child Cohort Study. Journal of Sports Sciences. ISSN 0264-0414. doi: 10.1080/02640414.2025.2609026. Full text in Research Archive
• Skullerud, Kristin Helene; Gjersvik, Petter; Pripp, Are Hugo; Qvigstad, Erik; Vangen, Siri & Helgesen, Anne Lise Ording (2025). Apremilast Versus Placebo for Genital Erosive Lichen Planus in Women: A Randomized Controlled Trial. Journal of Lower Genital Tract Disease. ISSN 1089-2591. 30(1), p. 60–65. doi: 10.1097/LGT.0000000000000915. Full text in Research Archive
• Pettersen, Silje; Falk, Ragnhild Sørum; Vangen, Siri & Nyfløt, Lill Trine (2025). Tone or tissue? A comparison of trends and risk factors of severe postpartum hemorrhage according to uterine atony or retained tissue in a hospital setting. PLOS ONE. 20(2). doi: 10.1371/journal.pone.0318770. Full text in Research Archive Show summary

  Objective To compare trends, outcomes and risk factors for severe postpartum hemorrhage (PPH) due to uterine atony and retained tissue separately. Study design This retrospective hospital-based study of severe PPH included deliveries from a 10-year cohort (2008–2017) and a four-year case-control group (2008–2011). Severe PPH was defined as an estimated blood loss of ≥1500 ml or a blood transfusion. Poisson regression was used to estimate the temporal trend in the 10-year cohort. Risk factors were investigated in the case-control group. We performed multinomial regression analysis to investigate associations between pregnancy characteristics and severe PPH caused by uterine atony and by retained tissue compared to controls without severe PPH. Results During the 10-year study period, 2.7% of all deliveries were complicated by severe PPH. Uterine atony without concurring retained tissue was the cause in 55.4%, while retained tissue was listed as a cause in 32.2% of the cases. Among women who received ≥ four units of blood products, retained tissue caused 42.6% of cases, and severe PPH resulting in a hysterectomy was caused by retained tissue in 61.2% of cases. The rate of severe PPH caused by uterine atony significantly increased during the study period with an estimated annual percentage change of 8.6%, while the increase in severe PPH due to retained tissue was non-significant. Risk factors associated only with uterine atony were multiple pregnancy, macrosomia, Asian ethnicity and operative delivery, while induction of labor, augmentation of labor, use of anticoagulants and assisted reproduction were associated with both uterine atony and retained tissue. Conclusion The observed increased rate of PPH in the study period was mainly driven by an increase in atonic PPH, while the rate of severe PPH caused by retained tissue remained stable. The proportion caused by retained tissue was highest among the most severe cases of PPH. The reason for the increase in severe PPH due to uterine atony, but not retained tissue was not clear, but we speculate that it may be a combination of increasing risk factors with increased awareness of PPH.

• Nordklev, Cecilie Bryn; Gjesdal, Ola; Gunnes, Nina; Holmstrøm, Henrik; Morken, Nils-Halvdan & Vangen, Siri [Show all 7 contributors for this article] (2024). Down syndrome and associated atrioventricular septal defects in a nationwide Norwegian cohort: Prevalence, time trends, and outcomes. Acta Obstetricia et Gynecologica Scandinavica. ISSN 0001-6349. 103(10), p. 2024–2030. doi: 10.1111/aogs.14932. Full text in Research Archive Show summary

  Introduction The prevalence of Down syndrome (DS) is approximately 1 per 1000 births and is influenced by increasing maternal age over the last few decades. DS is strongly associated with congenital heart defects (CHDs), especially atrioventricular septal defect (AVSD). Our objectives were to investigate the prevalence of live-born infants with DS having a severe CHD in the Norwegian population over the last 20 years and compare outcomes in infants with AVSD with and without DS. Material and Methods Information on all births from January 1, 2000 to December 31, 2019 was obtained from the Medical Birth Registry of Norway. We also obtained data on all infants with severe CHDs in Norway registered in Oslo University Hospital's Clinical Registry for Congenital Heart Defects during 2000–2019 and accessed individual-level patient data from the electronic hospital records of selected cases. Infants with AVSD and DS were compared to infants with AVSD without chromosomal defects. Crude and adjusted odds ratios (ORs) of infant mortality and need for surgery during the first year of life, with associated 95% confidence intervals (CIs), were estimated by logistic regression. Results A total of 1 177 926 infants were live-born in Norway during the study period. Among these, 1456 (0.1%) had DS. The prevalence of infants with DS having a severe CHDs was relatively stable, with a mean of 17 cases per year. The most common CHD associated with DS was AVSD (44.4%). Infants with AVSD and DS were more likely to have cardiac intervention during their first year of life compared to infants with AVSD without chromosomal defects (adjusted OR [aOR]: 2.52; 95% CI 1.27, 4.98). However, we observed no difference in infant mortality during first year of life between the two groups (aOR: 1.08; 95% CI 0.43, 2.70). Conclusions The prevalence of live-born infants with severe CHDs and DS has been stable in Norway across 20 years. Infants with AVSD and DS did not have higher risk of mortality during their first year of life compared to infants with AVSD without chromosomal defects, despite a higher risk of operative intervention.

• Skullerud, Kristin Helene; Gjersvik, Petter; Eberhard-Gran, Malin; Pripp, Are Hugo; Qvigstad, Erik & Vangen, Siri [Show all 7 contributors for this article] (2024). Sexual Distress and Quality of Life in Women With Genital Erosive Lichen Planus—A Cross-sectional Study. Journal of Lower Genital Tract Disease. ISSN 1089-2591. 29(1). doi: 10.1097/LGT.0000000000000847. Full text in Research Archive Show summary

  Objective: The study aimed to assess sexual distress and quality of life in women with moderate-to-severe genital erosive lichen planus (GELP). Materials and Methods: Thirty-six women with GELP were recruited at the Oslo University Hospital in Norway. The diagnosis was confirmed by a dermatologist with experience in vulvovaginal disease and based on characteristic clinical changes in the vulva and/or vagina, and biopsy results if available. Clinical severity was measured using the GELP score with a score ≥5 required for inclusion. Sexual distress was measured using the revised Female Sexual Distress Scale (FSDS-R), and quality of life was measured using the Dermatology Life Quality Index (DLQI). Topical steroid treatment was allowed. Results: The mean FSDS-R score was 22.7 (range 0–45) with 27 women reporting high scores for sexual distress (FSDS-R score >15). The mean DLQI score was 8.8 (range 1–19) with 15 women reporting a moderate impact (DLQI score 6–10), and 12 women reporting a very large impact (DLQI score 11–20) of GELP on their quality of life. No clear correlations were found between disease severity assessed by GELP scores and FSDS-R or DLQI scores. Age was not correlated with FSDS-R or DLQI scores. Conclusions: These results demonstrate that a substantial number of women with GELP experience sexual distress and a reduced quality of life.

• Støer, Nathalie Charlotte; Vangen, Siri; Singh, Deependra; Fortner, Renee T.; Hofvind, Solveig & Ursin, Giske [Show all 7 contributors for this article] (2024). Menopausal hormone therapy and breast cancer risk: a population-based cohort study of 1.3 million women in Norway. British Journal of Cancer. ISSN 0007-0920. 131(1), p. 126–137. doi: 10.1038/s41416-024-02590-1. Full text in Research Archive Show summary

  <p>BACKGROUND: It is important to monitor the association between menopausal hormone therapy (HT) use and breast cancer (BC) risk with contemporary estimates, and specifically focus on HT types and new drugs. <p><p>METHODS: We estimated hazard ratios (HR) of BC risk according to HT type, administration route and individual drugs, overall and stratified by body mass index (BMI), molecular subtype and detection mode, with non-HT use as reference. <p>RESULTS: We included 1,275,783 women, 45+ years, followed from 2004, for a median of 12.7 years. Oral oestrogen combined with daily progestin was associated with the highest risk of BC (HR 2.42, 95% confidence interval (CI) 2.31–2.54), with drug-specific HRs ranging from Cliovelle®: 1.63 (95% CI 1.35–1.96) to Kliogest®: 2.67 (2.37–3.00). Vaginal oestradiol was not associated with BC risk. HT use was more strongly associated with luminal A cancer (HR 1.97, 95% CI 1.86–2.09) than other molecular subtypes, and more strongly with interval (HR 2.00, 95% CI: 1.83–2.30) than screen-detected (HR 1.33, 95% CI 1.26–1.41) BC in women 50–71 years. HRs for HT use decreased with increasing BMI. <p>CONCLUSIONS: The use of oral and transdermal HT was associated with an increased risk of BC. The associations varied according to HT type, individual drugs, molecular subtype, detection mode and BMI.

• Varpula, Reetta; Äyräs, Outi; Aabakke, Anna J. M.; Klungsøyr, Kari; Svanvik, Teresia & Kanerva, Julia [Show all 22 contributors for this article] (2024). Early suppression policies protected pregnant women from COVID-19 in 2020: A population-based surveillance from the Nordic countries. Acta Obstetricia et Gynecologica Scandinavica. ISSN 0001-6349. 103(6), p. 1063–1072. doi: 10.1111/aogs.14808. Full text in Research Archive Show summary

  Introduction The Coronavirus 2019 Disease (COVID-19) pandemic reached the Nordic countries in March 2020. Public health interventions to limit viral transmission varied across different countries both in timing and in magnitude. Interventions indicated by an Oxford Stringency Index ≥50 were implemented early (March 13–17, 2020) in Denmark, Finland, Norway and Iceland, and on March 26, 2020 in Sweden. The aim of the current study was to assess the incidence of COVID-19-related admissions of pregnant women in the Nordic countries in relation to the different national public health strategies during the first year of the pandemic. Material and methods This is a meta-analysis of population-based cohort studies in the five Nordic countries with national or regional surveillance in the Nordic Obstetric Surveillance System (NOSS) collaboration: national data from Denmark, Finland, Iceland and Norway, and regional data covering 31% of births in Sweden. The source population consisted of women giving birth in the included areas March 1–December 31, 2020. Pregnant women with a positive SARS-CoV-2 PCR test ≤14 days before hospital admission were included, and admissions were stratified as either COVID-19-related or non-COVID (other obstetric healthcare). Information about public health policies was retrieved retrospectively. Results In total, 392 382 maternities were considered. Of these, 600 women were diagnosed with SARS-CoV-2 infection and 137 (22.8%) were admitted for COVID-19 symptoms. The pooled incidence of COVID-19 admissions per 1000 maternities was 0.5 (95% confidence interval [CI] 0.2 to 1.2, I2 = 77.6, tau2 = 0.68, P = 0.0), ranging from no admissions in Iceland to 1.9 admissions in the Swedish regions. Interventions to restrict viral transmission were less stringent in Sweden than in the other Nordic countries. Conclusions There was a clear variation in pregnant women's risk of COVID-19 admission across countries with similar healthcare systems but different public health interventions to limit viral transmission. The meta-analysis indicates that early suppression policies protected pregnant women from severe COVID-19 disease prior to the availability of individual protection with vaccines.

• Al-Zirqi, Iqbal Ahmad Abdelwahab & Vangen, Siri (2023). Pregnancies in Women with a Previous Complete Uterine Rupture. Obstetrics and Gynecology International. ISSN 1687-9589. doi: 10.1155/2023/9056489. Full text in Research Archive
• Voldner, Nanna; Eick, Frode & Vangen, Siri (2023). ‘Goodbye and good luck’ Midwifery care to pregnant undocumented migrants in Norway: A qualitative study. Sexual & Reproductive HealthCare. ISSN 1877-5756. 37(September), p. 1–6. doi: 10.1016/j.srhc.2023.100878. Full text in Research Archive Show summary

  Objective: To explore community midwives’ experiences caring for pregnant undocumented migrants seeking prenatal care in Norway. Method: Due to the relatively limited previous research and number of pregnant undocumented migrants we used an explorative approach through qualitative method. Ten community midwives were interviewed after snowball sampling in Oslo, the capital of Norway. The main themes emerged through a qualitative analysis of the transcripts, and meaning units were extracted. Results: Midwives with no prior experience with pregnant undocumented migrants expressed uncertainty regarding the women’s rights. In contrast, those midwives who had had prior experience with this group, developed their own solutions and enacted certain strategies to help them without any guidelines from their employer. All the midwives found it challenging to provide follow-up care to the undocumented migrants during pregnancy and postpartum. They also expressed concerns regarding increasing challenges creating clinical trusting relationships and restrictions and practices at public hospitals. Conclusions: To ensure adequate perinatal care, it is needed to reassure pregnant undocumented migrants free and safe care at all stages in the birth giving process. Community midwives need professional support in establishing trusting clinical relationships with pregnant undocumented migrants to reduce maternal stress and facilitate continuity in perinatal care.

• Natvik, Marianne; Gjelsvik, Bjørn E.; Vangen, Siri; Skjeie, Holgeir & Brekke, Mette (2023). Women's information needs about menopause: a cross-sectional survey in Norwegian general practice. British Journal of General Practice Open. 8(1), p. 1–8. doi: 10.3399/BJGPO.2023.0127. Full text in Research Archive Show summary

  Background Research indicates that providing women with information about menopause can improve their attitude towards menopause and symptom experience. Nevertheless, information shared on this topic is often arbitrary. Aim Examine women’s information needs about menopause, and understand if, when, and from whom they want information. Design &amp; setting A cross-sectional study among women in the waiting room of 54 general practice clinics in South-Eastern Norway, autumn 2022. Method Medical students recruited women in the clinics waiting room. A one-page study specific questionnaire was used, focusing on need for information about menopause. Results A total of 625 women were included, with a mean age of 44.4 years (SD 8.7). In all, 59% answered that they wanted information about menopause, and 81% of these wanted their general practitioner (GP) to inform them, from a median age of 45. According to the women, only 10% of GPs had addressed the topic. Higher education was a predictor for wanting information. A main driver of information needs was to help oneself in the present and in the future. In all, 33% did not want information. The main reasons were that they already possessed sufficient information, would take menopause as it comes, were too young, or were already postmenopausal. The gender of the GP did not influence the results. Conclusion Most women wanted information about menopause from their GP. The study emphasises the need for GPs to consider prioritising this discussion, and to keep up to date on recommendations and treatment options.

• Pettersen, Silje; Falk, Ragnhild Sørum; Vangen, Siri & Nyfløt, Lill Trine (2023). Exploring trends of severe postpartum haemorrhage: a hospital-based study. BMC Pregnancy and Childbirth. 23, p. 1–11. doi: 10.1186/s12884-023-05702-6. Full text in Research Archive Show summary

  Background Over the past two decades several high-income countries have reported increased rates of postpartum haemorrhage (PPH). Many of the studies are registry studies with limited access to detailed information. We aimed to explore trends of severe PPH in the largest labour ward in Norway during a 10-year period with a hospital based study. Our population constituted all women who gave birth after week 22 at Oslo University Hospital between 2008 and 2017. The main outcome measure was severe PPH, defined as registered blood loss greater than 1500 ml, or transfusion of blood products due to PPH. Methods We estimated the incidence of severe PPH and blood transfusions, and performed temporal trend analysis. We performed Poisson regression analysis to investigate associations between pregnancy characteristics and severe PPH, presented using crude incidence rate ratios (IRR) with 95% confidence intervals (CI)s. We also estimated annual percentage change of the linear trends. Results Among 96 313 deliveries during the 10-year study period, 2621 (2.7%) were diagnosed with severe PPH. The incidence rate doubled from 17.1/1000 to 2008 to 34.2/1000 in 2017. We also observed an increased rate of women receiving blood transfusion due to PPH, from 12.2/1000 to 2008 to 27.5/1000 in 2017. The rates of invasive procedures to manage severe PPH did not increase, and we did not observe a significant increase in the number of women defined with maternal near miss or massive transfusions. No women died due to PPH during the study period. Conclusion We found a significant increasing trend of severe PPH and related blood transfusions during the 10-year study period. We did not find an increase in massive PPH, or in invasive management, and we suspect that the rise can be at least partly explained by increased awareness and early intervention contributing to improved registration of severe PPH.

• Taraldsen, Sølvi; Vangen, Siri; Øian, Pål & Sørbye, Ingvil (2022). Risk of obstetric anal sphincter injury associated with female genital mutilation/cutting and timing of deinfibulation. Acta Obstetricia et Gynecologica Scandinavica. ISSN 0001-6349. 101(10), p. 1163–1173. doi: 10.1111/aogs.14424. Full text in Research Archive Show summary

  Introduction: A greater risk of obstetric anal sphincter injury has been reported among African migrants in several host countries compared with the general population. To what degree female genital mutilation/cutting affects this risk is not clear. In infibulated women, deinfibulation prevents anal sphincter injury. Whether the timing of deinfibulation affects the risk, is unknown. This study aimed to investigate the risks of anal sphincter injury associated with female genital mutilation/cutting and timing of deinfibulation in Norway, and to compare the rates of anal sphincter injury in Somaliborn women and the general population.<p> <p>Material and methods: In a historical cohort study, nulliparous Somali-born women who had a vaginal birth in the period 1990–2014 were identified by the Medical Birth Registry of Norway and data collected from medical records. Exposures were female genital mutilation/cutting status and deinfibulation before labor, during labor or no deinfibulation. The main outcome was obstetric anal sphincter injuries. <p>Results: Rates of obstetric anal sphincter injury did not differ significantly by female genital mutilation/cutting status (type 1–2: 10.2%, type 3: 11.3%, none: 15.2% P = 0.17). The total rate of anal sphincter injury was 10.3% compared to 5.0% among nulliparous women in the general Norwegian population. Women who underwent deinfibulation during labor had a lower risk than women who underwent deinfibulation before labor (odds ratio 0.48, 95% confidence interval 0.27–0.86, P = 0.01). <p>Conclusions: The high rate of anal sphincter injury in Somali nulliparous women was not related to type of female genital mutilation/cutting. Deinfibulation during labor protected against anal sphincter injury, whereas deinfibulation before labor was associated with a doubled risk. Deinfibulation before labor should not be routinely recommended during pregnancy

• Bremerthun, Silje Pettersen; Falk, Ragnhild Sørum; Vangen, Siri & Nyfløt, Lill Trine (2022). Peripartum hysterectomy due to severe postpartum hemorrhage: A hospital-based study. Acta Obstetricia et Gynecologica Scandinavica. ISSN 0001-6349. 101, p. 819–826. doi: 10.1111/aogs.14358. Full text in Research Archive Show summary

  Introduction A peripartum hysterectomy is typically performed as a lifesaving procedure in obstetrics to manage severe postpartum hemorrhage. Severe hemorrhages that lead to peripartum hysterectomies are mainly caused by uterine atony and placenta accreta spectrum disorders. In this study, we aimed to estimate the incidence, risk factors, causes and management of severe postpartum hemorrhage resulting in peripartum hysterectomies, and to describe the complications of the hysterectomies. Material and methods Eligible women had given birth at gestational week 23+0 or later and had a postpartum hemorrhage ≥1500 mL or a blood transfusion, due to postpartum hemorrhage, at Oslo University Hospital, Norway, between 2008 and 2017. Among the eligible women, this study included those who underwent a hysterectomy within the first 42 days after delivery. The Norwegian Medical Birth Registry provided the reference group. We used Poisson regression to estimate adjusted incidence rate ratios with 95% confidence intervals to identify clinical factors associated with peripartum hysterectomy. Results The incidence of hysterectomies with severe postpartum hemorrhage was 0.44/1000 deliveries (42/96313). Among the women with severe postpartum hemorrhage, 1.6% ended up with a hysterectomy (42/2621). Maternal age ≥40, previous cesarean section, multiple pregnancy and placenta previa were associated with a significantly higher risk of hysterectomy. Placenta accreta spectrum disorders were the most frequent cause of hemorrhage that resulted in a hysterectomy (52%, 22/42) and contributed to most of the complications following the hysterectomy (11/15 women with complications). Conclusions The rate of peripartum hysterectomies at Oslo University Hospital was low, but was higher than previously reported from Norway. Risk factors included high maternal age, previous cesarean section, multiple pregnancy and placenta previa, well known risk factors for placenta accreta spectrum disorders and severe postpartum hemorrhage. Placenta accreta spectrum disorders were the largest contributor to hysterectomies and complications.

• Eberhard-Gran, Malin Marie Cecilia; Engelsen, Lena Yri; Al-Zirqi, Iqbal Ahmad Abdelwahab & Vangen, Siri (2022). Depressive symptomer og fødselsopplevelse hos spedbarnsmødre under covid-19-pandemien. Tidsskrift for Den norske legeforening (Tidsskriftet). ISSN 0029-2001. 142(3), p. 1–9. doi: 10.4045/tidsskr.21.0450. Full text in Research Archive
• Ottesen, Hanna; Sørbye, Ingvil; Lindskog, Benedikte V; Vangen, Siri; Sundby, Johanne Sommerchild & Owe, Katrine Mari (2022). Keisersnitt blant utenlandsfødte kvinner med ulike utdanningsnivåer. Tidsskrift for Den norske legeforening (Tidsskriftet). ISSN 0029-2001. doi: 10.4045/tidsskr.22.0256. Full text in Research Archive Show summary

  BAKGRUNN Studier har vist at innvandrerkvinner, spesielt kvinner født i Afrika sør for Sahara, har høy forekomst av akutt keisersnitt. Samtidig varierer risikoen for planlagt og akutt keisersnitt med mors utdanningsnivå. Blant kvinner født i land i Afrika sør for Sahara og andre lav- og mellominntektsland er det en høyere andel med lav eller ingen utdanning sammenlignet med kvinner født i Norge. Vi ønsket derfor å undersøke sammenhengen mellom mors fødested, utdanningsnivå og risikoen for keisersnitt. MATERIALE OG METODE Studien tok utgangspunkt i alle fødsler i Norge registrert i Medisinsk fødselsregister i perioden 2008–17 koblet til data fra Statistisk sentralbyrå. Mors fødested, inndelt i fire kategorier, var eksponeringen. Endepunktet var planlagt eller akutt keisersnitt. Vi benyttet multinomial logistisk regresjon og stratifiserte analysene etter utdanningsnivå. Norskfødte kvinner utgjorde referansegruppen. RESULTATER Av 572 349 fødsler sto utenlandsfødte kvinner for 26,6 %. Keisersnitt utgjorde 15,1 % av alle fødslene. 9,6 % av alle fødslene var akutte keisersnitt. Norskfødte kvinner hadde den høyeste andelen planlagte keisersnitt (5,7 %), mens kvinner født i Afrika sør for Sahara hadde den høyeste andelen akutte keisersnitt (16,3 %). Blant kvinner med høyere utdanning var andelen akutte keisersnitt 8,3 % blant norskfødte kvinner og 18,1 % blant kvinner født i Afrika sør for Sahara (justert relativ risiko 2,41, 95 %-konfidensintervall 2,18 til 2,66). FORTOLKNING Utdanningsnivå påvirket risikoen for keisersnitt ulikt hos innvandrerkvinner og norskfødte kvinner.

• Jatta, Fatou; Sundby, Johanne Sommerchild; Vangen, Siri; Lindskog, Benedikte V; Sørbye, Ingvil & Owe, Katrine Mari (2021). Association between Maternal Origin, Pre-Pregnancy Body Mass Index and Caesarean Section: A Nation-Wide Registry Study. International Journal of Environmental Research and Public Health (IJERPH). ISSN 1661-7827. 18(11). doi: 10.3390/ijerph18115938. Full text in Research Archive Show summary

  Aims: To explore the association between maternal origin and birthplace, and caesarean section (CS) by pre-pregnancy body mass index (BMI) and length of residence. Methods: We linked records from 118,459 primiparous women in the Medical Birth Registry of Norway between 2013 and 2017 with data from the National Population Register. We categorized pre-pregnancy BMI (kg/m2) into underweight (<18.5), normal weight (18.5–24.9) and overweight/obese (≥25). Multinomial regression analysis estimated crude and adjusted relative risk ratios (RRR) with 95% confidence intervals (CI) for emergency and elective CS. Results: Compared to normal weight women from Norway, women from Sub-Saharan Africa and Southeast Asia/Pacific had a decreased risk of elective CS (aRRR = 0.57, 95% CI 0.37–0.87 and aRRR = 0.56, 0.41–0.77, respectively). Overweight/obese women from Europe/Central Asia had the highest risk of elective CS (aRRR = 1.42, 1.09–1.86). Both normal weight and overweight/obese Sub-Saharan African women had the highest risks of emergency CS (aRRR = 2.61, 2.28-2.99; 2.18, 1.81-2.63, respectively). Compared to women from high-income countries, the risk of elective CS was increasing with a longer length of residence among European/Central Asian women. Newly arrived migrants from Sub-Saharan Africa had the highest risk of emergency CS. Conclusion: Women from Sub-Saharan Africa had more than two times the risk of emergency CS compared to women originating from Norway, regardless of pre-pregnancy BMI.

• Taraldsen, Sølvi; Owe, Katrine Mari; Bødtker, Anne Sejersted; Bjørntvedt, Ida Waagsbø; Eide, Birgitte & Sandberg, Marit [Show all 10 contributors for this article] (2021). Omskjæring hos kvinner bosatt i Norge – konsekvenser og behandling. Tidsskrift for Den norske legeforening (Tidsskriftet). ISSN 0029-2001. 141(15). doi: 10.4045/tidsskr.21.0509. Full text in Research Archive Show summary

  BAKGRUNN Poliklinikktilbud for kvinner som har gjennomgått omskjæring finnes ved syv norske sykehus. I vår studie presenteres symptomer, funn og behandling hos kvinner som ble undersøkt ved poliklinikkene i perioden 2004–15. MATERIALE OG METODE Hvert sykehus identifiserte pasienter ved søk etter relevante diagnose- og behandlingskoder. Alle som hadde vært til undersøkelse ved poliklinikkene, ble inkludert. Data ble innhentet fra journaler. RESULTATER 913 kvinner ble inkludert. Median alder ved omskjæring var syv år og ved konsultasjon 26 år. Nær halvparten var gravide. De fleste (81 %) hadde type 3-omskjæring (infibulering). Av disse hadde 87 % gynekologiske plager. Blant kvinner med omskjæring type 1 og type 2 rapporterte henholdsvis 55 % og 70 % gynekologiske plager. I alt 64 % fikk kirurgisk behandling, hovedsakelig deinfibulering (98 %). Det var registrert få komplikasjoner etter deinfibulering. FORTOLKNING Hos mange yngre og ikke-gravide infibulerte kvinner kan omskjæringsrelaterte plager som kan behandles med deinfibulering, ha vært til stede fra barne- og ungdomsalder. Det finnes trolig et udekket behandlingsbehov blant omskårne kvinner, uavhengig av omskjæringstype.

• Engjom, Hilde Marie; Aabakke, Anna J. M.; Klungsøyr, Kari; Svanvik, Teresia; Äyräs, Outi & Jonasdottir, Eva [Show all 16 contributors for this article] (2021). COVID‐19 in pregnancy – characteristics and outcomes of pregnant women admitted to hospital because of SARS‐CoV‐2 infection in the Nordic countries. Acta Obstetricia et Gynecologica Scandinavica. ISSN 0001-6349. 100(9), p. 1611–1619. doi: 10.1111/aogs.14160. Full text in Research Archive Show summary

  Introduction Population-based studies about the consequences of SARS-CoV-2 infection (COVID-19) in pregnancy are few and have limited generalizability to the Nordic population and healthcare systems. Material and methods This study examines pregnant women with COVID-19 in the five Nordic countries. Pregnant women were included if they were admitted to hospital between 1 March and 30 June 2020 and had a positive SARS-CoV-2 PCR test ≤14 days prior to admission. Cause of admission was classified as obstetric or COVID-19-related. Results In the study areas, 214 pregnant women with a positive test were admitted to hospital, of which 56 women required hospital care due to COVID-19. The risk of admission due to COVID-19 was 0.4/1000 deliveries in Denmark, Finland and Norway, and 3.8/1000 deliveries in the Swedish regions. Women hospitalized because of COVID-19 were more frequently obese (p < 0.001) and had a migrant background (p < 0.001) compared with the total population of women who delivered in 2018. Twelve women (21.4%) needed intensive care. Among the 56 women admitted due to COVID-19, 48 women delivered 51 infants. Preterm delivery (n = 12, 25%, p < 0.001) and cesarean delivery (n = 21, 43.8%, p < 0.001) were more frequent in women with COVID-19 compared with women who delivered in 2018. No maternal deaths, stillbirths or neonatal deaths were reported. Conclusions The risk of admission due to COVID-19 disease in pregnancy was low in the Nordic countries. A fifth of the women required intensive care and we observed higher rates of preterm and cesarean deliveries. National public health policies appear to have had an impact on the risk of admission due to severe COVID-19 disease in pregnancy. Nordic collaboration is important in collecting robust data and assessing rare outcomes.

• Bains, Sukhjeet; Skråning, Susanne; Sundby, Johanne Sommerschild; Vangen, Siri; Sørbye, Ingvil & Lindskog, Benedikte V. (2021). Challenges and barriers to optimal maternity care for recently migrated women - a mixed-method study in Norway. BMC Pregnancy and Childbirth. 21(1), p. 1–14. doi: 10.1186/s12884-021-04131-7. Full text in Research Archive Show summary

  Background: Migrant women are at increased risk for complications related to pregnancy and childbirth, possibly due to inadequate access and utilisation of healthcare. Recently migrated women are considered a vulnerable group who may experience challenges in adapting to a new country. We aimed to identify challenges and barriers recently migrated women face in accessing and utilising maternity healthcare services. Methods: In the mixed-method MiPreg-study, we included recently migrated (≤ fve years) pregnant women born in low- or middle-income countries and healthcare personnel. First, we conducted 20 in-depth interviews with migrant women at Maternal and Child Health Centres (MCHC) and seven in-depth interviews with midwives working at either the hospital or the MCHCs in Oslo. Afterwards, we triangulated our fndings with 401 face-to-face questionnaires post-partum at hospitals among migrant women. The data were thematically analysed by grouping codes after careful consideration and consensus between the researchers. Results: Four main themes of challenges and barriers faced by the migrant women were identifed: (1) Navigating the healthcare system, (2) Language, (3) Psychosocial and structural factors, and (4) Expectations of care. Within the four themes we identifed a range of individual and structural challenges, such as limited knowledge about available healthcare services, unmet needs for interpreter use, limited social support and conficting recommendations for pregnancy-related care. The majority of migrant women (83.6%) initiated antenatal care in the frst trimester. Several of the challenges were associated with vulnerabilities not directly related to maternal health. Conclusion: A combination of individual, structural and institutional barriers hinder recently migrated women in achieving optimal maternal healthcare. Suggested strategies to address the challenges include improved provision of information about healthcare structure to migrant women, increased use of interpreter services, appropriate psycho-social support and strengthening diversity- and intercultural competence training among healthcare personnel

• Nyfløt, Lill Trine; Johansen, Marianne; Mulic-Lutvica, Ajlana; Gissler, Mika; Bødker, Birgit & Bremme, Katarina [Show all 8 contributors for this article] (2021). The impact of cardiovascular diseases on maternal deaths in the Nordic countries. Acta Obstetricia et Gynecologica Scandinavica. ISSN 0001-6349. 100, p. 1273–1279. doi: 10.1111/aogs.14104. Full text in Research Archive Show summary

  Introduction Cardiovascular diseases have become increasingly important as a cause of maternal death in the Nordic countries. This is likely to be associated with a rising incidence of pregnant women with congenital and acquired cardiac diseases. Through audits, we aim to prevent future maternal deaths by identifying causes of death and suboptimal factors in the clinical management. Material and methods Maternal deaths in the Nordic countries from 2005 to 2017 were identified through linked registers. The national audit groups performed case assessments based on hospital records, classified the cause of death, and evaluated the standards of clinical care provided. Key messages were prepared to improve treatment. Results We identified 227 maternal deaths, giving a maternal mortality rate of 5.98 deaths per 100 000 live births. The most common cause of death was cardiovascular disease (n = 36 deaths). Aortic dissection/rupture, myocardial disease, and ischemic heart disease were the most common diagnoses. In nearly 60% of the cases, the disease was not recognized before death. In more than half of the deaths, substandard care was identified (59%). In 11 deaths (31%), improvements to care that may have made a difference to the outcome were identified. Conclusions Between 2005 and 2017, cardiovascular diseases were the most common causes of maternal deaths in the Nordic countries. There appears to be a clear potential for a further reduction in these maternal deaths. Increased awareness of cardiac symptoms in pregnant women seems warranted.

• Sørbye, I.K.; Bains, Sukhjeet; Vangen, Siri; Sundby, Johanne Sommerschild; Lindskog, Benedikte V & Owe, Katrine Mari (2021). Obstetric anal sphincter injury by maternal origin and length of residence: a nationwide cohort study. BJOG: An International Journal of Obstetrics and Gynaecology. ISSN 1470-0328. 129(3), p. 423–431. doi: 10.1111/1471-0528.16985. Full text in Research Archive Show summary

  Objective: To estimate the association between maternal origin and obstetric anal sphincter injury (OASI), and assess if associations differed by length of residence. Design: Population-based cohort study. Setting: The Medical Birth Registry of Norway. Population: Primiparous women with vaginal livebirth of a singleton cephalic fetus between 2008 and 2017 (n = 188 658). Methods: Multivariable logistic regression models estimated adjusted odds ratios (aORs) for OASI with 95% CI by maternal region of origin and birthplace. We stratified models on length of residence and paternal birthplace. Main outcome measures: OASI. Results: Overall, 6373 cases of OASI were identified (3.4% of total cohort). Women from South Asia were most likely to experience OASI (6.2%; aOR 2.24, 95% CI 1.87–2.69), followed by those from Southeast Asia, East Asia & the Pacific (5.7%; 1.59, 1.37–1.83) and Sub-Saharan Africa (5.2%; 1.85, 1.55–2.20), compared with women originating from Norway. Among women born in the same region, those with short length of residence in Norway (0–4 years), showed the highest odds of OASI. Migrant women across most regions of origin had the lowest risk of OASI if they had a Norwegian partner. Conclusions: Primiparous women from Asian regions and Sub-Saharan Africa had up to two-fold risk of OASI, compared with women originating from Norway. Migrants with short residence and those with a foreign-born partner had higher risk of OASI, implying that some of the risk differential is due to sociocultural factors. Some migrants, especially new arrivals, may benefit from special attention during labour to reduce morbidity and achieve equitable outcomes.

• Bains, Sukhjeet; Sundby, Johanne Sommerchild; Lindskog, Benedikte V; Vangen, Siri; Diep, Lien My & Owe, Katrine Mari [Show all 7 contributors for this article] (2021). Satisfaction with maternity care among recent migrants: an interview questionnaire-based study. BMJ Open. 11(7). doi: 10.1136/bmjopen-2020-048077. Full text in Research Archive Show summary

  Objective: To examine factors associated with recently migrated women’s satisfaction with maternity care in urban Oslo, Norway. Design: An interview-based cross-sectional study, using a modified version of Migrant Friendly Maternity Care Questionnaire. Setting: Face-to-face interview after birth in two maternity wards in urban Oslo, Norway, from January 2019 to February 2020. Participants: International migrant women, ≤5 years length of residency in Norway, giving birth in urban Oslo, excluding women born in high-income countries. Primary outcome: Dissatisfaction of care during pregnancy and birth, measured using a Likert scale, grouped into satisfied and dissatisfied, in relation to socio-demographic/clinical characteristics and healthcare experiences. Secondary outcome: Negative healthcare experiences and their association with reason for migration. Results: A total of 401 women answered the questionnaire (87.6% response rate). Overall satisfaction with maternal healthcare was high. However, having a Norwegian partner, higher education and high Norwegian language comprehension were associated with greater odds of being dissatisfied with care. One-third of all women did not understand the information provided by the healthcare personnel during maternity care. More women with refugee background felt treated differently because of factors such as religion, language and skin colour, than women who migrated due to family reunification. Conclusions: Although the overall satisfaction was high, for certain healthcare experiences such as understanding information, we found more negative responses. The negative healthcare experiences and factors associated with satisfaction identified in this study have implications for health system planning, education of healthcare personnel and strategies for quality improvement.

• Bains, Sukhjeet; Sundby, Johanne Sommerchild; Lindskog, Benedikte V; Vangen, Siri & Sørbye, Ingvil (2021). Newly Arrived Migrant Women’s Experience of Maternity Health Information: A Face-to-Face Questionnaire Study in Norway. International Journal of Environmental Research and Public Health (IJERPH). ISSN 1661-7827. 18(14). doi: 10.3390/ijerph18147523. Full text in Research Archive Show summary

  Limited understanding of health information may contribute to an increased risk of adverse maternal outcomes among migrant women. We explored factors associated with migrant women’s understanding of the information provided by maternity staff, and determined which maternal health topics the women had received insufficient coverage of. We included 401 newly migrated women (≤5 years) who gave birth in Oslo, excluding migrants born in high-income countries. Using a modified version of the Migrant Friendly Maternity Care Questionnaire, we face-to-face interviewed the women postnatally. The risk of poor understanding of the information provided by maternity staff was assessed in logistic regression models, presented as adjusted odds ratios (aORs), with 95% confidence intervals (CI). The majority of the 401 women were born in European and Central Asian regions, followed by South Asia and North Africa/the Middle East. One-third (33.4%) reported a poor understanding of the information given to them. Low Norwegian language proficiency, refugee status, no completed education, unemployment, and reported interpreter need were associated with poor understanding. Refugee status (aOR 2.23, 95% CI 1.01–4.91), as well as a reported interpreter need, were independently associated with poor understanding. Women who needed but did not get a professional interpreter were at the highest risk (aOR 2.83, 95% CI 1.59–5.02). Family planning, infant formula feeding, and postpartum mood changes were reported as the most frequent insufficiently covered topics. To achieve optimal understanding, increased awareness of the needs of a growing, linguistically diverse population, and the benefits of interpretation services in health service policies and among healthcare workers, are needed.

• Taraldsen, Sølvi; Vangen, Siri; Øian, Pål & Sørbye, Ingvil (2021). Female genital mutilation/cutting, timing of deinfibulation, and risk of cesarean section. Acta Obstetricia et Gynecologica Scandinavica. ISSN 0001-6349. 100(4), p. 587–595. doi: 10.1111/aogs.14111. Full text in Research Archive Show summary

  Introduction The impact of female genital mutilation/cutting on obstetric outcomes in high-income countries is not clear. In general, women with female genital mutilation/cutting type 3 (infibulation) seem to be most at risk of adverse outcomes such as cesarean section. Deinfibulation is recommended to prevent obstetric complications. Whether the timing of this procedure affects the complication risk is not known. The aims of this study were, first, to examine the association between female genital mutilation/cutting and the risk of cesarean section in Norway, and, second, whether the timing of deinfibulation affected the cesarean section risk. Material and methods This was a historical cohort study of nulliparous Somali-born women who gave birth in Norway between 1990 and 2014. The Medical Birth Registry of Norway identified the women. Data were collected from medical records at 11 participating birth units. The exposures were female genital mutilation/cutting status and deinfibulation before pregnancy, during pregnancy, or no deinfibulation before labor onset. The main outcome was odds ratio (OR) of cesarean section. Type of cesarean section, primary indications, and neonatal outcomes were secondary outcomes. Results Women with female genital mutilation/cutting type 3 had lower risk of cesarean section compared with women with no female genital mutilation/cutting (OR 0.54, 95% CI 0.33-0.89 P = .02). Among the 1504 included women, the cesarean section rate was 28.0% and the proportion of emergency operations was 92.9%. Fetal distress was the primary indication in approximately 50% of cases, across the groups with different female genital mutilation/cutting status. Women who had no deinfibulation before labor onset had lower risk of cesarean section compared with those who underwent deinfibulation before or during pregnancy (OR 0.64, 95% CI 0.46-0.88 P = .01). Conclusions High risk of cesarean section in Somali nulliparous women was not related to the type of female genital mutilation/cutting in the present study. Deinfibulation before labor did not protect against cesarean section. Our findings indicate that nulliparous Somali women are at high risk of intrapartum complications. Future research should focus on measures to reduce maternal morbidity and on how timing of deinfibulation affects the outcomes of vaginal births.

• Waldum, Åsa; Jacobsen, Anne Flem; Lukasse, Mirjam; Staff, Anne Cathrine; Falk, Ragnhild Sørum & Vangen, Siri [Show all 7 contributors for this article] (2020). The provision of epidural analgesia during labor according to maternal birthplace: a Norwegian register study. BMC Pregnancy and Childbirth. 20(321). doi: 10.1186/s12884-020-03021-8. Full text in Research Archive Show summary

  Background: The provision of epidural analgesia during labor is ideally a shared decision between the woman and her health care provider. However, immigrant characteristics such as maternal birthplace could affect decision-making and thus access to pain relief. We aimed to assess disparities in the provision of epidural analgesia in planned vaginal birth according to maternal region of birth. Methods: We performed a nation-wide register study of 842,496 live-born singleton deliveries in Norway between 2000 and 2015. Maternal birthplace was categorized according to the Global Burden of Disease framework. The provision of epidural analgesia was compared in regression models stratified by parity and mode of delivery. Results: Compared to native-born women, primiparous women from Latin America/Caribbean countries with an instrumental vaginal delivery were most likely to be provided epidural analgesia (OR 2.12, 95%CI 1.69–2.66), whilst multiparous women from Sub-Saharan Africa with a spontaneous vaginal delivery were least likely to be provided epidural analgesia (OR 0.42, 95% C 0.39–0.44). Longer residence time was associated with a higher likelihood of being provided analgesia, whereas effects of maternal education varied by Global Burden of Disease group. Conclusions: Disparities in the likelihood of being provided epidural analgesia were observed by maternal birthplace. Further studies are needed to consider whether the identified disparities represent women’s own preferences or if they are the result of heterogeneous access to analgesia during labor.

• Al-Zirqi, Iqbal Ahmad Abdelwahab & Vangen, S. (2020). Prelabour uterine rupture: characteristics and outcomes. BJOG: An International Journal of Obstetrics and Gynaecology. ISSN 1470-0328. 127(13), p. 1637–1644. doi: 10.1111/1471-0528.16363. Full text in Research Archive
• Sørbye, Ingvil; Vangen, Siri; Juárez, Sol P; Bolumar, Francisco; Morisaki, Naho & Gissler, Mika [Show all 11 contributors for this article] (2019). Birthweight of babies born to migrant mothers - What role do integration policies play? SSM - Population Health. ISSN 2352-8273. 9. doi: 10.1016/j.ssmph.2019.100503. Full text in Research Archive
• Mgongo, Melina Bernard; Hussein, Tamara Hashim; Stray-Pedersen, Babill; Vangen, Siri; Msuya, Sia Emmanueli & Wandel, Margareta (2019). Facilitators and Barriers to Breastfeeding and Exclusive Breastfeeding in Kilimanjaro Region, Tanzania: A Qualitative Study. International Journal of Pediatrics. ISSN 1687-9740. 2019. doi: 10.1155/2019/8651010. Full text in Research Archive Show summary

  Background. Breastfeeding is the best way to feed infants. It is a simple intervention to improve child health and development. Despite its advantages, there is a low global rate of exclusive breastfeeding (EBF) and, in Kilimanjaro region, Tanzania, EBF is rarely practiced. The aim of this paper is to explore social and cultural factors that might influence the practice of breastfeeding and exclusive breastfeeding in Kilimanjaro region.Methods. A qualitative design was used. Three districts in Kilimanjaro region, namely, Same, Moshi Municipal Council, and Rombo, were selected. In each district three focus group discussions (FGDs) were conducted with mothers with infants aged 0-12 months.Results. A total of 78 mothers participated in the focus group discussions. A majority of the mothers were positive towards breastfeeding. They believed that it prevents child sickness, creates happiness, and is good for family economy. Despite the positive attitudes, the mothers revealed many perceptions that interfered with breastfeeding and exclusive breastfeeding. These included the following: breast milk is very light and has bad odor, breastfeeding may affect mothers appearance,chango(abdominal pain) has to be treated, there is fear of the evil eye when breastfeeding in public places, breast milk may become unclean, and there is a need of pauses in breastfeeding after the child has burped on the breast.Conclusion. There are beliefs that promote the practice of breastfeeding in this setting; these local beliefs could be used to develop breastfeeding messages to improve breastfeeding practices. However, there is also a need to address beliefs that interfere with the practice of exclusive breastfeeding in this setting.

• Collins, Sally L.; Alemdar, Bahrin; Beekhuizen, Heleen J. van; Bertholdt, Charline; Braun, Thorsten & Calda, Pavel [Show all 31 contributors for this article] (2019). Evidence-based guidelines for the management of abnormally invasive placenta: recommendations from the International Society for Abnormally Invasive Placenta. American Journal of Obstetrics and Gynecology. ISSN 0002-9378. 220(6), p. 511–526. doi: 10.1016/j.ajog.2019.02.054. Full text in Research Archive Show summary

  The worldwide incidence of abnormally invasive placenta is rapidly rising, following the trend of increasing cesarean delivery. It is a heterogeneous condition and has a high maternal morbidity and mortality rate, presenting specific intrapartum challenges. Its rarity makes developing individual expertise difficult for the majority of clinicians. The International Society for Abnormally Invasive Placenta aims to improve clinicians’ understanding and skills in managing this difficult condition. By pooling knowledge, experience, and expertise gained within a variety of different healthcare systems, the Society seeks to improve the outcomes for women with abnormally invasive placenta globally.

• Støer, Nathalie Charlotte; Botteri, Edoardo; Ghiasvand, Reza; Busund, Marit Katinka; Vangen, Siri & Lund, Eiliv [Show all 8 contributors for this article] (2019). Reproductive factors and risk of melanoma: a population-based cohort study. British Journal of Dermatology. ISSN 0007-0963. 181, p. 282–289. doi: 10.1111/bjd.17771. Full text in Research Archive Show summary

  Background: The association between reproductive factors and risk of cutaneous melanoma (CM) is unclear. We investigated this issue in the Norwegian Women and Cancer (NOWAC) cohort study. Objectives: To examine the association between the reproductive factors age at menarche, menstrual cycle length, parity, age at first and last birth, menopausal status, breastfeeding duration and length of ovulatory life and CM risk, overall and by histological subtypes and anatomical site Methods We followed 165,712 women aged 30-75 at inclusion from 1991-2007 to the end of 2015. Multivariable Cox regression was used to estimate hazard ratios (HRs) with 95% confidence intervals (CIs). Results: The mean age at cohort enrolment was 49 years. During a median follow-up of 18 years, 1,347 CM cases were identified. No reproductive factors were clearly associated with CM risk. When stratifying by histological subtype we observed significant heterogeneity (p = 0.01) in the effect of length of ovulatory life on the risk of superficial spreading melanoma (HR 1.02, 95% CI 1.01-1.04 per year increase) and nodular melanoma (HR 0.97, 95% CI 0.94-1.01 per year increase). When stratifying by anatomical site, menopausal status (HR 0.54, 95% CI 0.31-0.92, postmenopausal compared to premenopausal) and menstrual cycle length (HR 1.07, 95% CI 1.01-1.13, per day increase) were associated with CM of the trunk, and significant heterogeneity between anatomical sites was observed for menopausal status (p = 0.04). Conclusions: In this large population-based Norwegian cohort study, we did not find convincing evidence of an association between reproductive factors and risk of CM.

• Al-Zirqi, Iqbal Ahmad Abdelwahab; Daltveit, Anne Kjersti & Vangen, Siri (2019). Maternal outcome after complete uterine rupture. Acta Obstetricia et Gynecologica Scandinavica. ISSN 0001-6349. 98(8), p. 1024–1031. doi: 10.1111/aogs.13579. Full text in Research Archive Show summary

  Introduction: Complete uterine rupture, a rare peripartum complication, is often associated with a catastrophic outcome for both mother and child. However, few studies have investigated large datasets to evaluate maternal outcomes after complete ruptures, particularly in unscarred uteri. This paucity of studies is partly due to the rarity of both the event and the serious outcomes, such as peripartum hysterectomy and maternal death. The incidence of uterine rupture is expected to increase, due to increasing cesarean section rates worldwide. Thus, it is important to have more complete knowledge about the immediate maternal outcome following a complete uterine rupture. The objective was to identify maternal outcomes and their risk factors following complete uterine ruptures. Material and methods: This was a population‐based study using data from the Medical Birth Registry of Norway, the Patient Administration System and medical records. Maternities with complete uterine rupture after start of labor in Norway during 1967‐2008 (n = 247 births), identified among 2 209 506 women. Uterine ruptures were identified from both registries and were further studied through a review of medical records. Only complete ruptures were included in analysis. The associations between maternal outcomes and demographic and labor risk factors were estimated. Odds ratios (OR s) were determined with crude logistic regressions for each risk factor. Separate multivariable logistic regressions were performed to calculate adjusted odds ratios and 95% confidence intervals (CI s). Results: We identified 88 (35.6%) healthy mothers, 107 (43.3%) severe postpartum hemorrhages without hysterectomy, 51 (20.6%) peripartum hysterectomies, and three (1.2%) maternal deaths. Peripartum hysterectomy decreased significantly in the last years of study. Unscarred uterine ruptures significantly increased the risk of peripartum hysterectomy compared with scarred uterine ruptures (AOR 2.6, 95% CI 1.3‐5.3). Other factors that increased the risk of peripartum hysterectomy following rupture were: maternal age ≥35 years (AOR 2.3, 95% CI 1.1‐5.0), parity ≥3 vs parity 1‐2 (AOR 2.8, 95% CI 1.2‐6.7), and rupture detection after vaginal delivery (AOR 2.2, 95% CI 1.1‐4.8). Conclusions: Unscarred uteri, older maternal age, parity ≥3, and rupture detection after vaginal delivery showed the highest associations with the risk of peripartum hysterectomy after complete uterine rupture.

• Nyfløt, Lill Trine; Ellingsen, Liv; Yli, Branislava Markovic; Øian, Pål & Vangen, Siri (2018). Maternal deaths from hypertensive disorders: lessons learnt. Acta Obstetricia et Gynecologica Scandinavica. ISSN 0001-6349. 97(8), p. 976–987. doi: 10.1111/aogs.13357. Full text in Research Archive
• Mgongo, Melina Bernard; Hashim, Tamara Hussein; Stray-Pedersen, Babill; Vangen, Siri; Msuya, Sia Emmanueli & Wandel, Margareta (2018). "We give water or porridge, but we don't really know what the child wants:" A qualitative study on women's perceptions and practises regarding exclusive breastfeeding in Kilimanjaro region, Tanzania. BMC Pregnancy and Childbirth. 18:323, p. 1–9. doi: 10.1186/s12884-018-1962-3. Full text in Research Archive Show summary

  Background World Health Organization (WHO) recommends exclusive breastfeeding (EBF) as the optimal way to feed infants below 6 months of age. The benefits of EBF are well documented. However, in Tanzania, EBF is still rarely practised. This study explored the knowledge, attitudes and practises of EBF among mothers in Kilimanjaro region of northern Tanzania. Methods This is a qualitative research study. The three districts in Kilimanjaro region namely Same, Moshi Municipal Council and Rombo districts were selected. In each district, three focus group discussions (FGDs) with mothers of infants aged 0–12 months were conducted. A total of 78 mothers participated in the focus group discussion. Results The main result is that most of the mothers had a theoretical knowledge of the benefits of EBF but were not able to practise this knowledge for a range of reasons. The reasons for not practising EBF in real life included poor maternal nutrition, the pressure for women to return to work, inadequate knowledge about expressing breast milk, and perceived insufficiency of milk supply. Additionally, mothers received conflicting advice from a range of sources including close relatives, community members and health care providers, and they often choose the advice of their elders. Mothers also offered suggestions on ways to improve EBF including educating the community on the benefits of EBF. Conclusion The results show that the women need support from close relatives and employers to successfully practise EBF. This presents a need for involving close relatives in EBF interventions, as they are important sources of breastfeeding information in the community. Additionally, behavioural interventions that promote optimal breastfeeding practises might help to improve exclusive breastfeeding.

• Al-Zirqi, Iqbal Ahmad Abdelwahab; Daltveit, Anne Kjersti & Vangen, Siri (2018). Infant outcome after complete uterine rupture. American Journal of Obstetrics and Gynecology. ISSN 0002-9378. 219(1), p. 109.e1–109.e8. doi: 10.1016/j.ajog.2018.04.010. Full text in Research Archive
• Al-Zirqi, Iqbal Ahmad Abdelwahab; Daltveit, Anne Kjersti; Forsen, Lisa; Stray-Pedersen, Babill & Vangen, Siri (2017). Risk factors for complete uterine rupture. American Journal of Obstetrics and Gynecology. ISSN 0002-9378. 216(2), p. 165.e1–165.e8. doi: 10.1016/j.ajog.2016.10.017. Full text in Research Archive
• Reigstad, Marte Myhre; Storeng, Eleftheria (Ritsa) T.; Myklebust, Tor Åge; Oldereid, Nan Birgitte; Omland, Anne Katerine & Robsahm, Trude Eid [Show all 10 contributors for this article] (2017). Cancer risk in women treated with fertility drugs according to parity status- A registry-based cohort study. Cancer Epidemiology, Biomarkers and Prevention. ISSN 1055-9965. 26(6), p. 953–962. doi: 10.1158/1055-9965.EPI-16-0809. Full text in Research Archive
• Nyfløt, Lill Trine; Sandven, Irene; Stray-Pedersen, Babill; Pettersen, Silje; Al-Zirqi, Iqbal Ahmad Abdelwahab & Rosenberg, Margit [Show all 8 contributors for this article] (2017). Risk factors for severe postpartum hemorrhage: A case-control study. BMC Pregnancy and Childbirth. 17:17, p. 1–9. doi: 10.1186/s12884-016-1217-0. Full text in Research Archive Show summary

  Background In high-income countries, the incidence of severe postpartum hemorrhage (PPH) has increased. This has important public health relevance because severe PPH is a leading cause of major maternal morbidity. However, few studies have identified risk factors for severe PPH within a contemporary obstetric cohort. Methods We performed a case-control study to identify risk factors for severe PPH among a cohort of women who delivered at one of three hospitals in Norway between 2008 and 2011. A case (severe PPH) was classified by an estimated blood loss ≥1500 mL or the need for blood transfusion for excessive postpartum bleeding. Using logistic regression, we applied a pragmatic strategy to identify independent risk factors for severe PPH. Results Among a total of 43,105 deliveries occurring between 2008 and 2011, we identified 1064 cases and 2059 random controls. The frequency of severe PPH was 2.5% (95% confidence interval (CI): 2.32–2.62). The most common etiologies for severe PPH were uterine atony (60%) and placental complications (36%). The strongest risk factors were a history of severe PPH (adjusted OR (aOR) = 8.97, 95% CI: 5.25–15.33), anticoagulant medication (aOR = 4.79, 95% CI: 2.72–8.41), anemia at booking (aOR = 4.27, 95% CI: 2.79–6.54), severe pre-eclampsia or HELLP syndrome (aOR = 3.03, 95% CI: 1.74–5.27), uterine fibromas (aOR = 2.71, 95% CI: 1.69–4.35), multiple pregnancy (aOR = 2.11, 95% CI: 1.39–3.22) and assisted reproductive technologies (aOR = 1.88, 95% CI: 1.33–2.65). Conclusions Based on our findings, women with a history of severe PPH are at highest risk of severe PPH. As well as other established clinical risk factors for PPH, a history of severe PPH should be included as a risk factor in the development and validation of prediction models for PPH.

• Bjelland, Elisabeth Krefting; Owe, Katrine Mari; Nordeng, Hedvig Marie Egeland; Engdahl, Bo Lars; Kristiansson, Per & Vangen, Siri [Show all 7 contributors for this article] (2017). Does progestin-only contraceptive use after pregnancy affect recovery from pelvic girdle pain? A prospective population study. PLOS ONE. 12(9). doi: 10.1371/journal.pone.0184071. Full text in Research Archive Show summary

  Objective: To estimate associations of progestin-only contraceptives with persistent pelvic girdle pain 18 months after delivery. Methods Prospective population based cohort study during the years 2003–2011. We included 20,493 women enrolled in the Norwegian Mother and Child Cohort Study who reported pelvic girdle pain in pregnancy week 30. Data were obtained by 3 self-administered questionnaires and the exposure was obtained by linkage to the Prescription Database of Norway. The outcome was pelvic girdle pain 18 months after delivery. Results: Pelvic girdle pain 18 months after delivery was reported by 9.7% (957/9830) of women with dispense of a progestin-only contraceptive and by 10.5% (1114/10,663) of women without dispense (adjusted odds ratio 0.93; 95% CI 0.84–1.02). In sub-analyses, long duration of exposure to a progestin intrauterine device or progestin-only oral contraceptives was associated with reduced odds of persistent pelvic girdle pain (Ptrend = 0.021 and Ptrend = 0.005). Conversely, long duration of exposure to progestin injections and/or a progestin implant was associated with modest increased odds of persistent pelvic girdle pain (Ptrend = 0.046). Early timing of progestin-only contraceptive dispense following delivery (≤3 months) was not significantly associated with persistent pelvic girdle pain. Conclusions: Our findings suggest a small beneficial effect of progestin intrauterine devices and progestin-only oral contraceptives on recovery from pelvic girdle pain. We cannot completely rule out an opposing adverse effect of exposure to progestin injections and/or progestin implants. However, the modest increased odds of persistent pelvic girdle pain among these users could be a result of unmeasured confounding.

• Nyfløt, Lill Trine; Stray-Pedersen, Babill; Forsen, Lisa & Vangen, Siri (2017). Duration of labor and the risk of severe postpartum hemorrhage: A case-control study. PLOS ONE. 12(4). doi: 10.1371/journal.pone.0175306. Full text in Research Archive Show summary

  Objective Our main objective was to investigate the association between duration of active labor and severe postpartum hemorrhage. We examined the effect of the total duration of active labor, the effect of each stage of active labor, and the gradient effect of duration of labor on severe postpartum hemorrhage. Methods A case-control study was generated from a source population of all women admitted for delivery at Oslo University Hospital and Drammen Hospital in Buskerud municipality during the time period January 1, 2008 to December 31, 2011. The study population included all cases of severe postpartum hemorrhage (n = 859) and a random sample of controls (n = 1755). Severe postpartum hemorrhage was defined as postpartum blood loss >= 1500 mL or need for blood transfusion. Prolonged labor was defined as duration of active labor >12 hours according to the definition of the World Health Organization. We used logistic multi-variable regression in the analysis. Results We observed a significantly longer mean duration of labor in women who experienced severe postpartum hemorrhage compared to controls (5.4 versus 3.8 hours, p<0.001). Women with severe postpartum hemorrhage also had a longer duration of all stages of active labor compared to controls. The association between the duration of active labor and severe postpartum changed from a linear dose-response association to a threshold association after adjusting for augmentation with oxytocin, induction of labor, primiparity, and fever during labor. Compared to controls, women with severe postpartum hemorrhage were more likely to have a prolonged labor >12 hours (adjusted odds ratio = 2.44, 95% confidence interval: 1.69-3.53, p< 0.001). Conclusion Prolonged active labor (duration > 12 hours) was associated with severe postpartum hemorrhage. Increased vigilance seems required when the labor is prolonged to reduce the risk of severe postpartum hemorrhage.

• Mgongo, Melina Bernard; Chotta, Nikolas Albert Sagumo; Hashim, Tamara Hussein; Uriyo, Jacqueline; Damian, Damian J. & Stray-Pedersen, Babill [Show all 9 contributors for this article] (2017). Underweight, stunting and wasting among children in Kilimanjaro region, Tanzania; a population-based cross-sectional study. International Journal of Environmental Research and Public Health (IJERPH). ISSN 1661-7827. 14:509(5), p. 1–12. doi: 10.3390/ijerph14050509. Full text in Research Archive Show summary

  This study assessed the prevalence and risk factors associated with underweight, stunting and wasting among children aged 0–24 months in six districts of Kilimanjaro region, northern Tanzania. A cross-sectional population-based study using a multistage, proportionate to size sampling was conducted from June 2010 to March 2011. A structured questionnaire was used to collect sociodemographic, economic, feeding and child information. Anthropometric data were collected by trained field workers, and the data were used to assess child nutritional status. A total of 1870 children were enrolled in this study. The prevalence of children classified as underweight was 46.0%, stunting was 41.9%, and wasting was 24.7%. About 33% were both underweight and stunted, and 12% had all three conditions. In a multivariate logistic regression, child age, child being ill and birth weight were associated with all anthropometric indices. Child being breastfed was associated with being underweight and wasting. Mother’s education was associated with being underweight and stunting. Fathers aged 35+ years, and living in the Hai district was associated with stunting, and being female was associated with wasting. The prevalence of child undernutrition is high in this region. Strategies that target each risk factor for child undernutrition may help to reduce the problem in the region.

• Botteri, Edoardo; Støer, Nathalie Charlotte; Sakshaug, Solveig; Graff-Iversen, Sidsel; Vangen, Siri & Hofvind, Solveig [Show all 10 contributors for this article] (2017). Menopausal hormone therapy and colorectal cancer: a linkage between nationwide registries in Norway. BMJ Open. 7(11). doi: 10.1136/bmjopen-2017-017639. Full text in Research Archive Show summary

  Objectives: <br> With the present study, we aimed to investigate the association between menopausal hormone therapy (HT) and risk of colorectal cancer (CRC). <br> Setting: <br> Cohort study based on the linkage of Norwegian population-based registries. <br> Participants: <br> We selected 466822 Norwegian women, aged 55–79, alive and residing in Norway as of 1 January 2004, and we followed them from 2004 to 2008. Each woman contributed person-years at risk as non-user, current user and/or past HT user. <br> Outcome measures: <br> The outcome of interest was adenocarcinoma of the colorectal tract, overall, by anatomic site and stage at diagnosis. Incidence rate ratios (RRs) with 95%CIs were estimated by Poisson regression and were used to evaluate the association between HT and CRC incidence. <br> Results: <br> During the median follow-up of 4.8 years, 138 655 (30%) women received HT and 3799 (0.8%) incident CRCs occurred. Current, but not past, use of HT was associated with a lower risk of CRC (RR 0.88; 95% CI 0.80 to 0.98). RRs for localised, regionally advanced and metastatic CRC were 1.13 (95% CI 0.91 to 1.41), 0.81 (95% CI 0.70 to 0.94) and 0.79 (95% CI 0.62 to 1.00), respectively. RRs for current use of oestrogen therapy (ET) were 0.91 (95%CI 0.80 to 1.04) while RR for current use of combined oestrogen–progestin therapy (EPT) was 0.85 (95% CI 0.70 to 1.03), as compared with no use of HT. The same figures for ET and EPT in oral formulations were 0.83 (95% CI 0.68 to 1.03) and 0.86 (95% CI 0.71 to 1.05), respectively. <br> Conclusions: <br> In our nationwide cohort study, HT use lowered the risk of CRC, specifically the most advanced CRC.

• Botteri, Edoardo; Støer, Nathalie; Sakshaug, Solveig; Graff-Iversen, Sidsel; Vangen, Siri & Hofvind, Solveig [Show all 8 contributors for this article] (2017). Menopausal hormone therapy and risk of melanoma: Do estrogens and progestins have a different role? International Journal of Cancer. ISSN 0020-7136. 141(9), p. 1763–1770. doi: 10.1002/ijc.30878. Full text in Research Archive Show summary

  The association between use of menopausal hormone therapy (HT) and occurrence of skin malignant melanoma (SMM) is controversial. We investigated the issue in a nationwide cohort of 684,696 Norwegian women, aged 45–79 years, followed from 2004 to 2008. The study was based on linkage between Norwegian population registries. Multivariable Poisson regression models were used to estimate the effect of HT use, different HT types, routes of administration and doses of estrogen and progestin on the risk of SMM. During the median follow‐up of 4.8 years, 178,307 (26%) women used HT, and 1,476 incident SMM cases were identified. Current use of HT was associated with increased risk of SMM (rate ratios (RR) = 1.19; 95% confidence interval (CI) 1.03–1.37). Plain estrogen therapy was associated with an increased risk of SMM (RR 1.45; 95% CI 1.21–1.73), both for oral (RR 1.45; 95% CI 1.09–1.93) and vaginal (RR 1.44; 95% CI 1.14–1.84) formulations, while combined estrogen and progestin therapy (EPT) was not (RR 0.91; 95% CI 0.70–1.19). We performed a dose–response analysis of estrogen and progestin in women using tablets, and found that use of estrogens was associated with increased risk (RR 1.24; 95% CI 1.00–1.53 per 1 mg/day) and use of progestins with decreased risk (RR 0.71; 95% CI 0.57–0.89 per 10 mg/month) of SMM. In conclusion, estrogens were associated with increased risk of SMM, while combinations of estrogens and progestins were not. Our results suggest that estrogens and progestins might affect the risk of SMM in opposite ways.

• Sletner, Line; Jenum, Anne Karen; Yajnik, Chittaranjan S; Mørkrid, Kjersti; Nakstad, Britt & Jensen, Odd H. [Show all 8 contributors for this article] (2017). Fetal growth trajectories in pregnancies of European and South Asian mothers with and without gestational diabetes, a population-based cohort study. PLOS ONE. 12(3). doi: 10.1371/journal.pone.0172946. Full text in Research Archive Show summary

  Objective Our aim was to examine the impact of gestational diabetes (GDM), from before the GDM-diagnosis is made, on fetal growth trajectories, and to compare it in Europeans and South Asians; two ethnic groups with dissimilar fetal growth patterns. Methods We studied European (n = 349) and South Asian (n = 184) pregnant women, from the population-based STORK-Groruddalen cohort in Oslo, Norway. Mothers were enrolled in early pregnancy, screened for GDM in gestational week 28 ±2, and classified as “non-GDM”, “mild GDM” or “moderate/severe GDM”. We measured fetal head circumference, abdominal circumference and femur length by ultrasound, and estimated fetal weight in gestational week 24, 32 and 37, and performed corresponding measurements at birth. Results In non-GDM pregnancies, South Asian fetuses (n = 156) had a slower growth from gestational week 24, compared with Europeans (n = 310). More than two thirds of the European mothers later diagnosed with GDM were overweight or obese in early pregnancy, while this was not observed in South Asians. Fetuses of GDM mothers tended to be smaller than fetuses of non-GDM mothers in week 24, but thereafter grew faster until birth. This pattern was especially pronounced in fetuses of South Asian mothers with moderate/severe GDM. In week 24 these fetuses had a -0.95 SD (95% CI: -1.53, -0.36) lower estimated fetal weight than their non-GDM counterparts. In contrast, at birth they were 0.45 SD (0.09, 0.81) larger. Conclusions Offspring of GDM mothers were smaller in mid pregnancy, but subsequently grew faster until birth, compared with offspring of non-GDM mothers. This pattern was most prominent in South Asian mothers with moderate to severe GDM. However, the most remarkable characteristic of these fetuses was not a large size at birth, but the small size in mid pregnancy, before the GDM diagnosis was set.

• Nyfløt, Lill Trine; Sandven, Irene; Oldereid, Nan Birgitte; Stray-Pedersen, Babill & Vangen, Siri (2017). Assisted reproductive technology and severe postpartum haemorrhage: a case–control study. BJOG: An International Journal of Obstetrics and Gynaecology. ISSN 1470-0328. 124(8), p. 1198–1205. doi: 10.1111/1471-0528.14471. Full text in Research Archive
• Sletner, Line; Kiserud, Torvid; Vangen, Siri; Nakstad, Britt & Jenum, Anne Karen (2017). Effects of applying universal fetal growth standards in a Scandinavian multi-ethnic population. Acta Obstetricia et Gynecologica Scandinavica. ISSN 0001-6349. 97(2), p. 168–179. doi: 10.1111/aogs.13269. Full text in Research Archive Show summary

  Introduction: The question of whether universal growth charts can be used in multi‐ethnic settings is of general interest. The Intergrowth‐21st fetal growth and newborn size standards are suggested to represent optimal fetal growth regardless of country origin. Our aim was to examine whether women fulfilling the strict Intergrowth‐21st inclusion criteria were healthier, showed less ethnic differences in fetal growth and newborn size, and less adverse perinatal outcomes. Material and methods: Data were drawn from a population‐based multi‐ethnic cohort of 823 presumably healthy pregnant women in Oslo, Norway. We assessed differences in fetal and neonatal gestational age specific z‐scores and compared maternal health parameters, pregnancy and birth complications between pregnancies fulfilling and not fulfilling the Intergrowth‐21st criteria. Results: Only 21% of pregnancies enrolled in our cohort fulfilled the Intergrowth‐21st criteria. Fetal growth deviated substantially from the new standards, in particular for ethnic Europeans. Ethnic differences persisted in pregnancies fulfilling the criteria. In South Asian fetuses, estimated fetal weight was −0.60 SD (95% confidence interval −1.00, −0.20) lower at 24 gestational weeks, and birthweight was −0.62 SD (−0.95, −0.29) lower, compared with ethnic Europeans. Corresponding numbers for Middle‐East/North Africans were −0.13 (−0.62, 0.36) and −0.60 (−1.00, −0.20). Maternal health indicators and birth complications were similar in women fulfilling and not fulfilling the criteria, but the relation depended on ethnic origin. Conclusions: In an urban multi‐ethnic Norwegian population, applying an extensive list of criteria to define “healthy” pregnancies excludes the majority of women but does not cancel ethnic differences in fetal growth.

• Berg, Rigmor; Taraldsen, Sølvi; Said, Maryan; Sørbye, Ingvil & Vangen, Siri (2017). Reasons for and Experiences With Surgical Interventions for Female Genital Mutilation/Cutting (FGM/C): A Systematic Review. Journal of Sexual Medicine. ISSN 1743-6095. 14(8), p. 977–990. doi: 10.1016/j.jsxm.2017.05.016. Full text in Research Archive Show summary

  Background: Because female genital mutilation/cutting (FGM/C) leads to changes in normal genital anatomy and functionality, women are increasingly seeking surgical interventions for their FGM/C-related concerns. <br>Aim: To conduct a systematic review of empirical quantitative and qualitative research on interventions for women with FGM/C-related complications. <br>Methods: We conducted systematic searches up to May 2016 in 16 databases to obtain references from different disciplines. We accepted all study designs consisting of girls and women who had been subjected to FGM/C and that examined a reparative intervention for a FGM/C-related concern. We screened the titles, abstracts, and full texts of retrieved records for relevance. Then, we assessed the methodologic quality of the included studies and extracted and synthesized the study data. <br>Outcomes: All outcomes were included. <br>Results: Of 3,726 retrieved references, 71 studies including 7,291 women were eligible for inclusion.We identified three different types of surgical intervention: defibulation or surgical separation of fused labia, excision of a cyst with or without some form of reconstruction, and clitoral or clitoral-labial reconstruction. Reasons for seeking surgical interventions consisted of functional complaints, sexual aspirations, esthetic aspirations, and identity recovery. The most common reasons for defibulation were a desire for improved sexual pleasure, vaginal appearance, and functioning. For cyst excision, cystic swelling was the main reason for seeking excision; for reconstruction, the main reason was to recover identity. Data on women’s experiences with a surgical intervention are sparse, but we found that women reported easier births after defibulation. Our findings also suggested that most women were satisfied with defibulation (overall satisfaction ¼ 50e100%), typically because of improvements in their sexual lives. <br>Conversely, the results suggested that defibulation had low social acceptance and that the procedure created distress in some women who disliked the new appearance of their genitalia. Most women were satisfied with clitoral reconstruction, but approximately one third were dissatisfied with or perceived a worsening in the esthetic look. <br>Clinical Translation: The information health care professionals give to women who seek surgical interventions for FGM/C should detail the intervention options available and what women can realistically expect from such interventions <br>Strengths and Limitations: The systematic review was conducted in accordance with guidelines, but there is a slight possibility that studies were missed. <br>Conclusion: There are some data on women’s motivations for surgery for FGM/C-related concerns, but little is known about whether women are satisfied with the surgery, and experiences appear mixed.

• Vangen, Siri; Bødker, Birgit; Ellingsen, Liv; Saltvedt, Sissel; Gissler, Mika & Geirsson, Reynir T. [Show all 7 contributors for this article] (2017). Maternal deaths in the Nordic countries. Acta Obstetricia et Gynecologica Scandinavica. ISSN 0001-6349. 96(9), p. 1112–1119. doi: 10.1111/aogs.13172. Full text in Research Archive
• Berg, Rigmor; Taraldsen, Sølvi; Said, Maryan; Sørbye, Ingvil & Vangen, Siri (2017). The effectiveness of surgical interventions for women with FGM/C: a systematic review. BJOG: An International Journal of Obstetrics and Gynaecology. ISSN 1470-0328. 125(3), p. 278–287. doi: 10.1111/1471-0528.14839. Full text in Research Archive Show summary

  <p><i>Background</i><br> Female genital mutilation/cutting (FGM/C) changes normal genital functionality and can cause complications. There is an increasing demand for treatment of FGM/C‐related complications.</p> <p><i>Objectives</i><br> We conducted a systematic review of empirical quantitative research on the outcomes of interventions for women with FGM/C‐related complications.</p> <p><i>Search strategy</i><br> A search specialist searched 16 electronic databases.</p> <p><i>Selection criteria</i><br> Selection was performed independently by two researchers. We accepted quantitative studies that examined the outcome of an intervention for an FGM/C‐related concern.</p> <p><i>Data collection and analysis</i><br> We extracted data into a pre‐designed form, calculated effect estimates, and performed meta‐analyses.</p> <p><i>Main results</i><br> We included 62 studies (5829 women), which investigated the effect of defibulation, excision of cysts, and clitoral reconstruction. Meta‐analyses of defibulation versus no defibulation showed a significantly lower risk of caesarean section (relative risk, RR: 0.33; 95% confidence interval, 95% CI: 0.25–0.45) and perineal tears with defibulation: second‐degree tear (RR: 0.44, 95% CI: 0.24–0.79), third‐degree tear (RR: 0.21, 95% CI: 0.05–0.94), fourth‐degree tear (RR: 0.06, 95% CI: 0.01–0.41). The meta‐analyses detected no significant differences in obstetric outcomes of antenatal versus intrapartum defibulation. Except for one study, none of the studies on the excision of cysts indicated any complications, and the results were deemed favourable. Reconstructive surgery resulted in a visible clitoris in about 77% of women. Most women self‐reported improvements in their sexual life, but up to 22% experienced a worsening in sexuality‐related outcomes after reconstruction.</p> <p><i>Conclusions</i><br> Women with FGM/C who seek therapeutic surgery should be informed about the scarcity of evidence for benefits and the potential harms of the available procedures.

• Majak, Guri Bårdstu; Reisæter, Anna Varberg; Zucknick, Manuela; Lorentzen, Bjørg; Vangen, Siri & Henriksen, Tore [Show all 7 contributors for this article] (2017). Preeclampsia in kidney transplanted women; Outcomes and a simple prognostic risk score system. PLOS ONE. 12:e0173420(3), p. 1–11. doi: 10.1371/journal.pone.0173420. Full text in Research Archive
• Bjelland, Elisabeth Krefting; Owe, Katrine Mari; Pingel, Ronnie; Kristiansson, Per; Vangen, Siri & Eberhard-Gran, Malin (2016). Pelvic pain after childbirth: a longitudinal population study. Pain. ISSN 0304-3959. 157(3), p. 710–716. doi: 10.1097/j.pain.0000000000000427. Full text in Research Archive
• Owe, Katrine Mari; Bjelland, Elisabeth Krefting; Stuge, Britt; Orsini, Nicola; Eberhard-Gran, Malin & Vangen, Siri (2016). Exercise level before pregnancy and engaging in high-impact sports reduce the risk of pelvic girdle pain: a population-based cohort study of 39 184 women. British Journal of Sports Medicine. ISSN 0306-3674. 50(13), p. 817–822. doi: 10.1136/bjsports-2015-094921. Full text in Research Archive
• Roman, Martha; Graff-Iversen, Sidsel; Weiderpass, Elisabete; Vangen, Siri; Sakshaug, Solveig & Hofvind, Solveig [Show all 7 contributors for this article] (2016). Postmenopausal hormone therapy and breast cancer prognostic characteristics: A linkage between nationwide registries. Cancer Epidemiology, Biomarkers and Prevention. ISSN 1055-9965. 25(11), p. 1464–1473. doi: 10.1158/1055-9965.EPI-16-0240. Full text in Research Archive
• Majak, Guri Bårdstu; Sandven, Irene; Lorentzen, Bjørg; Vangen, Siri; Reisæter, Anna Varberg & Henriksen, Tore [Show all 7 contributors for this article] (2016). Pregnancy outcomes following maternal kidney transplantation: a national cohort study. Acta Obstetricia et Gynecologica Scandinavica. ISSN 0001-6349. 95(10), p. 1153–1161. doi: 10.1111/aogs.12937. Full text in Research Archive
• Al-Zirqi, Iqbal Ahmad Abdelwahab; Stray-Pedersen, Babill; Forsen, Lisa; Daltveit, Anne Kjersti & Vangen, Siri (2016). Uterine rupture: Trends over 40 years. BJOG: An International Journal of Obstetrics and Gynaecology. ISSN 1470-0328. 123(5), p. 780–787. doi: 10.1111/1471-0528.13394. Full text in Research Archive
• Owe, Katrine Mari; Nystad, Wenche; Stigum, Hein; Vangen, Siri & Bø, Kari (2016). Exercise during pregnancy and risk of Cesarean delivery in nulliparous women: A large population-based cohort study. American Journal of Obstetrics and Gynecology. ISSN 0002-9378. 215(6), p. 791.e1–791.e13. doi: 10.1016/j.ajog.2016.08.014. Full text in Research Archive Show summary

  Background: Vaginal delivery for the first birth is of great importance for further obstetric performance for the individual woman. Given the rising cesarean delivery (CD) rates worldwide over the past decades, the search for modifiable factors associated with CD is needed. Exercise may be a modifiable factor associated with type of delivery, but the results of previous studies are not conclusive. Objective: To investigate the association between exercise during pregnancy and CD, both acute and elective, in nulliparous women. Study design: A population-based cohort study involving 39,187 nulliparous women with a singleton pregnancy enrolled in the Norwegian Mother and Child Cohort Study (MoBa) between 2000 and 2009. All women answered two questionnaires in pregnancy weeks 17 and 30. Acute and elective CD were obtained from the Medical Birth Registry of Norway. Information on exercise frequency and type was assessed prospectively by questionnaires in pregnancy weeks 17 and 30. Generalized linear models estimated risk differences (RD) of acute and elective CD for different frequencies and types of exercise during pregnancy weeks 17 and 30. We used restricted cubic splines to examine dose-response associations of exercise frequency and acute CD. A test for non-linearity was also conducted. Results: The total CD rate was 15.4% (n=6030), of which 77.8% (n=4689) was acute CD. Exercise during pregnancy was associated with a reduced risk of CD, particularly for acute CD. A nonlinear association was observed for exercise frequency in weeks 17 and 30 and risk of acute CD (test for nonlinearity, P =0.003 and P =0.027, respectively). The largest risk reduction was observed for acute CD among women exercising more than five times weekly during weeks 17 (-2.2 percent) and 30 (-3.6 percent) compared to non-exercisers (test for trend P<.001). Reporting high impact exercises in weeks 17 and 30 was associated with the greatest reduction in risk of acute CD (-3.0 and -3.4 percent, respectively). Conclusion: Compared to non-exercisers, regular exercise and high impact exercises during pregnancy are associated with reduced risk of having an acute CD in first-time mothers.

• Merry, Lisa; Vangen, Siri & Small, Rhonda (2016). Caesarean births among migrant women in high-income countries. Best Practice & Research: Clinical Obstetrics & Gynaecology. ISSN 1521-6934. 32, p. 88–99. doi: 10.1016/j.bpobgyn.2015.09.002. Full text in Research Archive
• Herstad, Lina; Klungsøyr, Kari; Skjaerven, Rolv; Tanbo, Tom Gunnar; Forsen, Lisa & Åbyholm, Thomas [Show all 7 contributors for this article] (2016). Elective cesarean section or not? Maternal age and risk of adverse outcomes at term: A population-based registry study of low-risk primiparous women. BMC Pregnancy and Childbirth. 16. doi: 10.1186/s12884-016-1028-3. Full text in Research Archive Show summary

  Background Maternal age at delivery and cesarean section rates are increasing. In older women, the decision on delivery mode may be influenced by a reported increased risk of surgical interventions during labor and complications with increasing maternal age. We examined the association between maternal age and adverse outcomes in low-risk primiparous women, and the risk of adverse outcomes by delivery modes, both planned and performed (elective and emergency cesarean section, operative vaginal delivery, and unassisted vaginal delivery) in women aged ≥ 35 years. Methods A population-based registry study was conducted using data from the Medical Birth Registry of Norway and Statistics Norway including 169,583 low-risk primiparas with singleton, cephalic labors at ≥ 37 weeks during 1999 − 2009. Outcomes studied were obstetric blood loss, maternal transfer to intensive care units, 5-min Apgar score, and neonatal complications. We adjusted for potential confounders using relative risk models and multinomial logistic regression. Results Most adverse outcomes increased with increasing maternal age. However, the increase in absolute risks was low, except for moderate obstetric blood loss and transfer to the neonatal intensive care unit (NICU). Operative deliveries increased with increasing maternal age and in women aged ≥ 35 years, the risk of maternal complications in operative delivery increased. Neonatal adverse outcomes increased mainly in emergency operative deliveries. Moderate blood loss was three times more likely in elective and emergency cesarean section than in unassisted vaginal delivery, and twice as likely in operative vaginal delivery. Low Apgar score and neonatal complications occurred two to three times more often in emergency operative deliveries than in unassisted vaginal delivery. However, comparing outcomes after elective cesarean section and planned vaginal delivery, only moderate blood loss (higher in elective cesarean section), neonatal transfer to NICU and neonatal infections (both higher in planned vaginal delivery) differed significantly. Conclusions Most studied adverse outcomes increased with increasing maternal age, as did operative delivery. Although emergency operative procedures were associated with an increased risk of adverse outcomes, the absolute risk difference in complications between the modes of delivery was low for the majority of outcomes studied.

• Reigstad, Marte Myhre; Larsen, Inger Kristin; Myklebust, Tor Åge; Robsahm, Trude Eid; Oldereid, Nan Birgitte & Omland, Anne Katerine [Show all 9 contributors for this article] (2015). Cancer risk among parous women following assisted reproductive technology. Human Reproduction. ISSN 0268-1161. 30(8), p. 1952–1963. doi: 10.1093/humrep/dev124. Full text in Research Archive
• Herstad, Lina; Klungsøyr, Kari; Skjaerven, Rolv; Tanbo, Tom Gunnar; Forsen, Lisa & Åbyholm, Thomas [Show all 7 contributors for this article] (2015). Maternal age and emergency operative deliveries at term: a population-based registry study among low-risk primiparous women. BJOG: An International Journal of Obstetrics and Gynaecology. ISSN 1470-0328. 122(12), p. 1642–1651. doi: 10.1111/1471-0528.12962. Full text in Research Archive
• Størksen, Hege Therese; Niegel, Susan; Adams, Samantha Salvesen; Vangen, Siri & Eberhard-Gran, Malin (2015). Fear of childbirth and elective caesarean section: a population-based study. BMC Pregnancy and Childbirth. 15. doi: 10.1186/s12884-015-0655-4. Full text in Research Archive Show summary

  Background This population-based cohort study aimed to investigate the demographic and psychosocial characteristics associated with fear of childbirth and the relative importance of such fear as a predictor of elective caesarean section. Methods A sample of 1789 women from the Akershus Birth Cohort in Norway provided data collected by three self-administered questionnaires at 17 and 32 weeks of pregnancy and 8 weeks postpartum. Information about the participants’ childbirths was obtained from the hospital records. Results Eight percent of the women reported fear of delivery, defined as a score of ≥85 on the Wijma Delivery Expectancy Questionnaire. Using multivariable logistic regression models, a previous negative overall birth experience exerted the strongest impact on fear of childbirth, followed by impaired mental health and poor social support. Fear of childbirth was strongly associated with a preference for elective caesarean section (aOR 4.6, 95 % CI 2.9–7.3) whereas the association of fear with performance of caesarean delivery was weaker (aOR 2.4, 95 % CI 1.2–4.9). The vast majority (87 %) of women with fear of childbirth did not, however, receive a caesarean section. By contrast, a previous negative overall birth experience was highly predictive of elective caesarean section (aOR 8.1, 95 % CI 3.9–16.7) and few women without such experiences did request caesarean section. Conclusions Results suggest that women with fear of childbirth may have identifiable vulnerability characteristics, such as poor mental health and poor social support. Results also emphasize the need to focus on the subjective experience of the birth to prevent fear of childbirth and elective caesarean sections on maternal request. Regarding the relationship with social support, causality has to be interpreted cautiously, as social support was measured at 8 weeks postpartum only.

• Bjelland, Elisabeth Krefting; Owe, Katrine Mari; Stuge, Britt; Vangen, Siri & Eberhard-Gran, Malin (2015). Breastfeeding and pelvic girdle pain: a follow-up study of 10 603 women 18 months after delivery. BJOG: An International Journal of Obstetrics and Gynaecology. ISSN 1470-0328. 122(13), p. 1765–1771. doi: 10.1111/1471-0528.13118. Full text in Research Archive
• Sørbye, Ingvil; Daltveit, Anne Kjersti; Sundby, Johanne; Stoltenberg, Camilla & Vangen, Siri (2015). Caesarean section by immigrants' length of residence in Norway: a population-based study. European Journal of Public Health. ISSN 1101-1262. 25(1), p. 78–84. doi: 10.1093/eurpub/cku135. Full text in Research Archive
• Roman, Martha; Sakshaug, Solveig; Graff-Iversen, Sidsel; Vangen, Siri; Weiderpass, Elisabete & Ursin, Giske [Show all 7 contributors for this article] (2015). Postmenopausal hormone therapy and the risk of breast cancer in Norway. International Journal of Cancer. ISSN 0020-7136. 138(3), p. 584–593. doi: 10.1002/ijc.29810. Full text in Research Archive
• Vandraas, Kathrine; Vikanes, Åse Vigdis; Støer, Nathalie; Troisi, Rebecca; Stephansson, Olof & Sørensen, Henrik Toft [Show all 10 contributors for this article] (2015). Hyperemesis gravidarum and risk of cancer in offspring, a Scandinavian registry-based nested case-control study. BMC Cancer. 15. doi: 10.1186/s12885-015-1425-4. Full text in Research Archive
• Sletner, Line; Rasmussen, Svein; Jenum, Anne Karen; Nakstad, Britt; Jensen, Odd H. & Vangen, Siri (2015). Ethnic differences in fetal size and growth in a multi-ethnic population. Early Human Development. ISSN 0378-3782. 91(9), p. 547–554. doi: 10.1016/j.earlhumdev.2015.07.002. Full text in Research Archive
• Vandraas, Kathrine; Grjibovski, Andrej; Støer, Nathalie; Troisi, Rebecca; Stephansson, Olof & Ording, Anne Gulbech [Show all 9 contributors for this article] (2015). Hyperemesis gravidarum and maternal cancer risk, a scandinavian nested case-control study. International Journal of Cancer. ISSN 0020-7136. 137(5), p. 1209–1216. doi: 10.1002/ijc.29475. Full text in Research Archive
• Vangen, Siri; Ellingsen, Liv; Andersgaard, Alice Beathe; Jacobsen, Anne Flem; Lorentzen, Bjørg & Nyfløt, Lill Trine [Show all 10 contributors for this article] (2014). Mødredødsfall i Norge 2005-09. Tidsskrift for Den norske legeforening (Tidsskriftet). ISSN 0029-2001. 134(8), p. 836–839. doi: 10.4045/tidsskr.13.0203. Full text in Research Archive
• Eidem, Ingvild; Vangen, Siri; Henriksen, Tore; Vollset, Stein Emil; Hanssen, Kristian Folkvord & Joner, Geir [Show all 7 contributors for this article] (2014). Discrepancy in term calculation from second trimester ultrasound scan versus last menstrual period in women with type 1 diabetes. Acta Obstetricia et Gynecologica Scandinavica. ISSN 0001-6349. 93(8), p. 809–816. doi: 10.1111/aogs.12422. Full text in Research Archive
• Henriksen, Lena; Schei, Berit; Vangen, Siri & Lukasse, Mirjam (2014). Sexual violence and neonatal outcome: a Norwegian population-based cohort study. BMJ Open. 4(10). doi: 10.1136/bmjopen-2014-005935. Full text in Research Archive Show summary

  Objective The objective of this study was to explore the association between sexual violence and neonatal outcomes. Design National cohort study. Setting Women were recruited to the Norwegian Mother and Child Cohort Study (MoBa) while attending routine ultrasound examinations from 1999 to 2008. Population A total of 76 870 pregnant women. Methods Sexual violence and maternal characteristics were self-reported in postal questionnaires during pregnancy. Neonatal outcomes were retrieved from the Medical Birth Registry of Norway (MBRN). Risk estimations were performed with linear and logistic regression analysis. Outcome measures: gestational age at birth, birth weight, preterm birth (PTB), low birth weight (LBW) and small for gestational age (SGA). Results Of 76 870 women, 18.4% reported a history of sexual violence. A total of 4.7% delivered prematurely, 2.7% had children with a birth weight <2500 g and 8.1% children were small for their gestational age. Women reporting moderate or severe sexual violence (rape) had a significantly reduced gestational length (2 days) when the birth was provider-initiated in an analysis adjusted for age, parity, education, smoking, body mass index and mental distress. Those exposed to severe sexual violence had a significantly reduced gestational length of 0.51 days with a spontaneous start of birth. Crude estimates showed that severe sexual violence was associated with PTB, LBW and SGA. When controlling for the aforementioned sociodemographic and behavioural factors, the association was no longer significant. Conclusions Sexual violence was not associated with adverse neonatal outcomes. Moderate and severe violence had a small but significant effect on gestational age; however, the clinical influence of this finding is most likely limited. Women exposed to sexual violence in this study reported more of the sociodemographic and behavioural factors associated with PTB, LBW and SGA compared with non-abused women.

• Urquia, Marcelo; Glazier, Richard; Gagnon, Anita J.; Mortensen, Laust H.; Andersen, Anne-Marie Nybø & Janevic, Teresa [Show all 37 contributors for this article] (2014). Disparities in pre-eclampsia and eclampsia among immigrant women giving birth in six industrialised countries. BJOG: An International Journal of Obstetrics and Gynaecology. ISSN 1470-0328. 121(12), p. 1492–1500. doi: 10.1111/1471-0528.12758. Full text in Research Archive
• Henriksen, Lena; Schei, Berit; Vangen, Siri & Lukasse, Mirjam (2014). Sexual violence and mode of delivery: a population-based cohort study. BJOG: An International Journal of Obstetrics and Gynaecology. ISSN 1470-0328. 121(10), p. 1237–1244. doi: 10.1111/1471-0528.12923. Full text in Research Archive Show summary

  Objective: This study aimed to explore the association between sexual violence and mode of delivery. Design: National cohort study. Setting: Women presenting for routine ultrasound examinations were recruited to the Norwegian Mother and Child Cohort Study (MoBa) between 1999-2008. Population: 74 059 pregnant women. Methods: Sexual violence was self-reported during pregnancy using postal questionnaires. Mode of delivery, other maternal birth outcomes and covariates were retrieved from the Medical Birth Registry of Norway. Risk estimations were performed using multivariable logistic regression analysis. Main Outcome Measures: Mode of delivery and selected maternal birth outcomes. Results: Of 74 059 women, 18.4% reported a history of sexual violence. A total of 10% had an operative vaginal birth, 4.9% elective caesarean section (CS), and 8.6% had an emergency CS. Severe sexual violence (rape) was associated with elective CS, AOR 1.56 (95% CI 1.18-2.05) for nulliparous women and 1.37 (1.06-1.76) for multiparous women. Those exposed to moderate sexual violence had a higher risk of emergency CS, AOR 1.31 (1.07-1.60) and 1.41 (1.08-1.84) for nulli- and multiparous women, respectively. No association was found between sexual violence and operative vaginal birth, except for a lower risk among multiparous women reporting mild sexual violence, AOR 0.73 (0.60-0.89). Analysis of other maternal outcomes showed a reduced risk of episiotomy for women reporting rape and a higher frequency of induced labour. Conclusions: Women with a history of rape had higher odds of elective CS and induction and significantly fewer episiotomies.

• Mørkrid, Kjersti; Jenum, Anne Karen; Berntsen, Sveinung; Sletner, Line; Richardsen, Kåre Rønn & Vangen, Siri [Show all 8 contributors for this article] (2014). Objectively recorded physical activity and the association with gestational diabetes. Scandinavian Journal of Medicine & Science in Sports. ISSN 0905-7188. 24(5), p. e389–e397. doi: 10.1111/sms.12183. Full text in Research Archive Show summary

  The aim of this population-based study was to assess the association between objectively recorded physical activity (PA) in early gestation and gestational diabetes mellitus (GDM) identified at 28 weeks of gestation in a multiethnic cohort of healthy pregnant women in Oslo, Norway. In total, 759 women were included. In early gestation (<20 weeks), light-, moderate-, and vigorousintensity PA and number of steps were objectively recorded (SenseWear™ Armband Pro3), and selfreported PA, demographics, and anthropometrics were collected. The 75-g oral glucose tolerance test was performed at 28 weeks of gestation. Women with GDM had fewer objectively recorded steps (mean 7964 steps/day vs 8879 steps/day, P < 0.001) and minutes of moderate-tovigorous-intensity PA (median 62 min/day vs 75 min/day, P = 0.004) in early gestation than women without GDM. Additionally, 30% of women with GDM compared with 44% (P < 0.001) of women without GDM self-reported regular PA before pregnancy. The significant inverse association between objectively recorded steps per day in early gestation and GDM persisted after adjustment for ethnic origin, weeks of gestation, age, parity, prepregnancy BMI, early life socioeconomic position, and self-reported regular PA before pregnancy. The adjusted odds ratio for GDM decreased 19% per standard deviation (3159 steps) increase in objectively recorded steps per day (P = 0.039). Daily life PA in early gestation measured as steps/day was associated with lower risk of GDM.

• Sletner, Line; Jenum, Anne Karen; Mørkrid, Kjersti; Vangen, Siri; Holme, Ingar Morten K & Birkeland, Kåre I. [Show all 7 contributors for this article] (2014). Maternal Life Course Socio-Economic Position and Offspring Body Composition at Birth in a Multi-Ethnic Population. Paediatric and Perinatal Epidemiology. ISSN 0269-5022. 28(5), p. 445–454. doi: 10.1111/ppe.12137. Full text in Research Archive
• Sørbye, Ingvil; Daltveit, Anne Kjersti; Sundby, Johanne & Vangen, Siri (2014). Preterm subtypes by immigrants' length of residence in Norway: A population-based study. BMC Pregnancy and Childbirth. 14. doi: 10.1186/1471-2393-14-239. Full text in Research Archive Show summary

  Background: The reduction of the preterm delivery (PTD) rate is a maternal and child health target. Elevated rates have been found among several immigrant groups, but few studies have distinguished between PTD according to the mode of birth start. In addition, migrants’ birth outcomes have further been shown to be affected by the time in residence; however, the association to PTD subtypes has not previously been assessed. In this study we examined if the risk of spontaneous and non-spontaneous, or iatrogenic, PTD among immigrants in Norway varied according to the length of residence and the country of birth, and compared with the risks among the majority population. Methods: We linked population-based birth and immigration data for 40 709 singletons born to immigrant women from Iraq, Pakistan, the Philippines, Somalia, Sri Lanka and Vietnam and 868 832 singletons born to non-immigrant women from 1990–2009. Associations between the length of residence and subtypes of PTD were estimated as relative risks (RRs) with 95% confidence intervals (CIs) from multivariable models. Results: In total, 48 191 preterm births occurred. Both spontaneous and non-spontaneous PTD rates were higher among immigrants (4.8% and 2.0%) than among non-immigrants (3.6% and 1.6%). Only non-spontaneous PTD was associated with longer lengths of residence (p trend <0.001). Recent immigrants (<5 years of residence) and non-immigrants had a similar risk of non-spontaneous PTD, whereas immigrants with lengths of residence of 5–9 years, 10–14 years and ≥15 years had adjusted RRs of 1.18 [95% CI 1.03,1.35], 1.43 [95% CI 1.20,1.71] and 1.66 [95% CI 1.41,1.96]. The association was reduced after further adjustments for maternal and infant morbidity. Conversely, the risk of spontaneous PTD among immigrants was not mitigated by length of residence, but varied with country of birth according to the duration of pregnancy in term births. Conclusions: Non-spontaneous PTD increased with the length of residence whereas spontaneous PTD remained elevated regardless of the length of residence. Policies to improve birth outcomes in ethnically mixed populations should address the modifiable causes of PTD rather than aiming to reduce absolute PTD rates.

• Sørbye, Ingvil; Stoltenberg, Camilla; Sundby, Johanne; Daltveit, Anne Kjersti & Vangen, Siri (2014). Stillbirth and infant death among generations of Pakistani immigrant descent: a population-based study. Acta Obstetricia et Gynecologica Scandinavica. ISSN 0001-6349. 93(2), p. 168–174. doi: 10.1111/aogs.12303. Full text in Research Archive
• Al-Zirqi, Iqbal Ahmad Abdelwahab; Stray-Pedersen, Babill; Forsen, Lisa; Daltveit, Anne Kjersti & Vangen, Siri (2013). Validation study of uterine rupture registration in the Medical Birth Registry of Norway. Acta Obstetricia et Gynecologica Scandinavica. ISSN 0001-6349. 92(9), p. 1086–1093. doi: 10.1111/aogs.12148. Full text in Research Archive
• Fretheim, Atle; Odgaard-Jensen, Jan; Røttingen, John-Arne; Reinar, Liv Merete; Vangen, Siri & Tanbo, Tom Gunnar (2013). The impact of an intervention programme employing a hands-on technique to reduce the incidence of anal sphincter tears: interrupted time-series reanalysis. BMJ Open. 3(10). doi: 10.1136/bmjopen-2013-003355. Full text in Research Archive

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• Andreassen, Silje Malen; Costa, Denise Reis; Laine, Katariina; Evenson, Kelly R.; Vangen, Siri & Owe, Katrine Mari (2025). Twins on board: How does carrying two affect physical activity levels? Norsk Epidemiologi, Supplement. ISSN 0803-4206. 33(Supplement 1), p. 8–8. doi: https:/www.ntnu.no/ojs/index.php/norepid. Full text in Research Archive Show summary

  Introduction: Few longitudinal population-based studies have described physical activity patterns in women pregnant with twins, and studies on physical activity including the period after birth are lacking. We need knowledge of physical activity patterns in women pregnant with twins to develop physical activity recommendations. Aims: To describe stability and change in leisure-time physical activity (LTPA) from pre-pregnancy, through pregnancy and up to 18 months after birth in women pregnant with twins and compare patterns of LTPA by parity. Methods: We included 1,796 women pregnant with twins from the Norwegian Mother, Father and Child Cohort Study. LTPA was self-reported using a validated questionnaire in pregnancy weeks 17 and 30 and six and 18 months after birth. The women reported frequency of 14 different types of physical activities. Participants were eligible if they had a twin pregnancy, returned the first questionnaire, and reported LTPA at least once. To identify latent classes, we fitted a generalized latent class model including a quadratic term and with intercept and slope varying across individuals. We report estimated latent class-specific mean trajectories of LTPA for the total sample and stratified by parity. Results: Two latent classes were identified: stable low-to-moderate LTPA (76.6%) and high LTPA (23.4%). In the high LTPA class, levels of LTPA decreased from pre-pregnancy to gestational week 30. LTPA increased after birth, but not to pre-pregnancy levels. The highly active class had a higher proportion of nulliparous women (59.9%), while the low-to-moderately active class had a higher proportion of multiparous women (53.9%). Conclusions: This is the first population-based study exploring longitudinal LTPA in women pregnant with twins. Despite the heavy burden associated with twin pregnancy, we observed relatively stable moderate to high levels of LTPA from pre-pregnancy, through pregnancy, and up to 18 months after birth. The potential consequences of physical activity in twin pregnancy on maternal and fetal health remain unexplored, and further research on physical activity in twin pregnancies are needed.

• Andreassen, Silje Malen; Costa, Denise Reis; Laine, Katariina; Evenson, Kelly R.; Vangen, Siri & Owe, Katrine Mari (2025). How do physical activity levels differ in twin and singleton pregnancies? European Journal of Public Health. ISSN 1101-1262. 35(Supplement_4). doi: 10.1093/eurpub/ckaf161.1712. Full text in Research Archive Show summary

  Background: Twin pregnancy has been a contraindication to physical activity. Therefore, we lack population-based data describing physical activity in these pregnancies. We aimed to describe physical activity in women with twin and singleton pregnancies from pre-pregnancy through pregnancy and up to 18 months after birth. Methods: We used a population-based cohort including 1,938 twin and 109,370 singleton pregnancies in the Norwegian Mother, Father and Child Cohort Study (1999-2008). Frequency of 14 different types of leisure-time physical activities (LTPA) were self-reported using a validated questionnaire in pregnancy weeks 17 and 30 and at six and 18 months after birth. We performed descriptive statistics, including median weekly frequency of LTPA with interquartile range (IQR), and proportions of women reporting LTPA at least once weekly by plurality. Preliminary results: LTPA in women pregnant with twins declined from 4.00 times weekly (IQR: 2.50-6.25) pre-pregnancy to 2.25 times weekly (1.00-3.00) in pregnancy week 30. Corresponding frequencies for women with singletons were 4.00 (2.25-6.25) and 3.00 (1.25-4.25). The proportion of women reporting LTPA at least once weekly only differed in twin compared to singleton pregnancies in week 30, 61% and 70% respectively. In week 30, 10% of women pregnant with twins reported no LTPA compared to 3% of women with singletons. Eighteen months after birth, both women delivering twins and singletons resumed pre-pregnancy levels of LTPA. The most common types of LTPA were strolling and brisk walking in both groups of women. Conclusions: Patterns and types of LTPA were similar in women with twin and singleton pregnancies, except in pregnancy week 30 where levels of LTPA were lower in women carrying twins. This is the first population-based study on LTPA in women pregnant with twins. Thus, we need knowledge on who remains physically active, why physical activity changes, and potential consequences of physical activity in twin pregnancy. Key messages: • Women pregnant with twins were less physically active compared to women pregnant with singletons late in pregnancy. • Identifying physically inactive women and potential consequences of the decline in physical activity in women pregnant with twins is needed.

• Sørbye, Ingvil Krarup; Hagemann, Cecilie Therese & Vangen, Siri (2024). Senfølger etter omskjæring og helsehjelp i Norge. In Johansen, R. Elise B (Eds.), Kvinnelig omskjæring/kjønnslemlestelse i Norge; Kunnskap og praksis. Universitetsforlaget. ISSN 9788215069494. p. 237–249. doi: 10.18261/9788215069487-24-13. Full text in Research Archive Show summary

  I dette kapittelet presenterer vi funn fra studier i Norge om langtidsefekter etter kvinnelig omskjæring. Resultatene viser høy forekomst av underlivsplager og svangerskapskomplikasjoner som hastekeisersnitt og alvorlige fødselsrifter. Spesialisert helsehjelp finnes, men kun som tilbud om undersøkelse og åpningskirurgi. Det synes imidlertid å være behov også for smertekartlegging og behandling samt psykoseksuell rådgiving.

• Topranin, Virginia De Martin; Brørs, Gunhild; Bye, Anja & Vangen, Siri (2024). Har kvinner i Norge god kunnskap om risiko for hjerteinfarkt? [Internet]. Kvinnehelsebloggen. Full text in Research Archive
• Støer, Nathalie Charlotte; Botteri, Edoardo; Busund, Marit Katinka; Ghiasvand, Reza; Vangen, Siri & Lund, Eiliv [Show all 8 contributors for this article] (2021). Menopausal hormone therapy and risk of melanoma: a population-based cohort study. British Journal of Dermatology. ISSN 0007-0963. doi: 10.1111/bjd.20640. Full text in Research Archive
• Finholt, Hege Cathrine & Vangen, Siri (2016). Er kjønn likt fordelt i medisinsk kunnskap? Dagens medisin. ISSN 1501-4290. Full text in Research Archive
• Al-Zirqi, Iqbal Ahmad Abdelwahab; Stray-Pedersen, Babill; Forsen, Lisa; Daltveit, Anne Kjersti & Vangen, Siri (2016). Authors' reply re: Uterine rupture: Trends over 40 years. BJOG: An International Journal of Obstetrics and Gynaecology. ISSN 1470-0328. 123(6), p. 1033–1033. doi: 10.1111/1471-0528.13631. Full text in Research Archive
• Bjelland, Elisabeth Krefting; Owe, Katrine Mari; Pingel, Ronnie; Kristiansson, Per; Vangen, Siri & Eberhard-Gran, Malin (2016). Pelvic pain after childbirth: a longitudinal study. Full text in Research Archive
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