Digital Public Defence: Ole Aleksander Dyrkorn Ole Aleksander Dyrkorn at Institute of Clinical Medicine will be defending the thesis “The Impact of Childbirth before and after Mid-Urethral Sling Surgery: New Knowledge derived from Norwegian Health Registries” for the degree of PhD (Philosophiae Doctor).

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Photo: Ole Aleksander Dyrkorn

The public defence will be held as a video conference over Zoom.

The defence will follow regular procedure as far as possible, hence it will be open to the public and the audience can ask ex auditorio questions when invited to do so.

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Download Zoom here

Due to copyright reasons, an electronic copy of the thesis must be ordered from the faculty. In order for the faculty to have time to process the order, it must be received by the faculty no later than 2 days prior to the public defence. Orders received later than 2 days before the defence will not be processed. Inquiries regarding the thesis after the public defence must be addressed to the candidate.

Order a digital copy of the thesis here

Digital Trial Lecture – time and place

See Digital Trial Lecture.

Adjudication committee

  • First opponent: Professor Niels Klarskov, University of Copenhagen
  • Second opponent: Professor Jone Trovik, University of Bergen
  • Third member and chair of the evaluation committee: Professor II Anna Marie Ellström Engh, University of Oslo

Chair of the Defence

Professor Emeritus Guttorm Haugen, University of Oslo

Principal Supervisor

Professor II Rune Svenningsen, University of Oslo


Stress urinary incontinence (SUI) is a common pelvic floor disorder, substantially impacting women's quality of life, productivity, socializing, and sexuality. Childbirth, especially operative vaginal birth, is considered a significant risk factor. Surgical treatment for SUI is usually recommended when conservative treatment options have failed. Mid-urethral slings (MUS) have been established as the standard surgical treatment for SUI. Women, who have not completed childbearing, are usually advised to postpone surgical treatment, as a subsequent pregnancy is believed to impose a high risk of SUI recurrence.

This thesis's main aim was to increase the knowledge of the potential clinical impact of pregnancies before and after mid-urethral sling operations by combining data from two nationwide longitudinal cohorts, including 23,421 women undergoing MUS between 1998 - 2016. Furthermore, we wanted to validate the national Norwegian Female Incontinence Registry (NFIR) data quality to ensure that the registry was a reliable tool for quality control and scientific research.

This thesis demonstrates that the NFIR has a high degree of accuracy and is valid as a research tool. Furthermore, by combining data from NFIR and the Medical Birth Registry of Norway, we have shown that the long-term outcomes for women giving birth after MUS are reassuring, independent of delivery mode. Also, we found that obstetrical factors associated with SUI development do not seem to impact the short-term outcomes of primary MUS operations. However, being nulliparous was an exception to this conclusion, indicating a different underlying SUI pathogenesis in these women. 

Based on this thesis's findings, MUS seems to be a feasible option for women who have not completed childbearing if the indication for surgery is strong and conservative options have failed.

Additional information

Contact the research support staff.

Published Jan. 10, 2022 2:15 PM - Last modified Jan. 11, 2022 3:21 PM