Controversial ultrasound in week 12

In December 2011, the Norwegian Council for Quality Improvement and Priority Setting in Health Care decided, by a narrow margin, to advise that all pregnant women be offered an ultrasound in week 11-13. The Council evaluated the cost and health benefits of early ultrasounds.

No indisputable health benefit

As part of its evaluation process, the Council asked the Norwegian Knowledge Centre for the Health Services (NOKC) to evaluate the health benefits, diagnostic neutrality and economic consequences of offering early ultrasounds. NOKC formed a working group with representatives from relevant fields of expertise.

The working group's report, which was published on 16 January 2012, concludes that there is no documentation of early ultrasounds having beneficial health effects, although such effects cannot be discounted.

Goals remain unchanged

One of the experts who participated in the preparation of this report was Professor of obstetric aid and women's diseases at the Institute of Clinical Medicine, University of Oslo (UiO) and clinical consultant at the Oslo University Hospital (OUS), Annetine Staff. On Monday, 16 January, she presented the report alongside post-doctor, midwife and genetic adviser at OUS, Anne Kaasen. The report was presented during an open meeting on early ultrasounds organised by the Norwegian Directorate of Health on behalf of the Ministry of Health and Care Services.

The findings showed that routine early ultrasounds largely have the same goals as the current ultrasounds offered in week 17-19, but that the earlier ultrasound can more easily uncover risks of chromosomal abnormalities and whether twins share a placenta. Previous research has suggested that early ultrasounds may have benefits relating to the detection of congenital heart defects, but NOKC found no studies confirming a direct link between offers of early ultrasound and the prognosis for foetuses with heart defects.

May save twins

A shared placenta is a risk factor for twin-to-twin transfusion syndrome. Between 15 and 20 percent of monozygotic twins have a shared placenta and some shared blood circulation. Twin-to-twin transfusion syndrome occurs in about 12-15 percent of such cases. The syndrome may lead to one twin bleeding into the other, and one twin may "steal" nutrition from the other. Untreated, the syndrome has an 80 percent mortality rate.

Though twin-to-twin transfusion syndrome is one of few foetal situations that can be treated in utero, the NOKC working group did not find any studies showing that early ultrasounds have a direct effect on the prognosis for these twins.

Nevertheless, Staff believes that early ultrasounds may have an important effect in relation to the syndrome, as resources can be concentrated on the pregnancies that need extra attention:

"If the placenta status for twins is determined in an early ultrasound, the ultrasound follow-up of twin pregnancies can be adapted to this type of pregnancy, which are the twin pregnancies that carry the most risk", says Staff.

"The current practice, in which an ultrasound in week 17-19 is the only ultrasound on offer in the public health care system, more twin pregnancies must be followed up closely, because the signs of the status of the placenta are no longer present."

 

"This is not medical progress"

Ola Didrik Saugstad is Professor of Paediatrics and Director of the Department of Pediatric Research at UiO/OUS. Saugstad does not research ultrasounds or foetal diagnostics, but the high-profile paediatrician has been heavily involved in the public debate on the topic.

"The way I see it, it has not been shown that early ultrasounds represent a medical advance", says Saugstad. He believes that early ultrasounds will have a marginal effect on twin-to-twin transfusion syndrome.

"A German study recently showed that with current technology and practices, in which this condition is treated with laser surgery after week 18, the twins have a survival rate of more than 80 percent. If early ultrasounds increase the survival rate by as much as 10 percent, this represents 5-6 more children a year profiting from this system", Saugstad says.

But he is not immovable in his views.

"Though I have been critical of early ultrasounds because I believe the medical benefits are minimal, I must emphasise that whenever research shows that early ultrasounds have a clear health benefit, I will support their introduction. Of course, in such an event we must also consider all the associated ethical questions."

"A question of values"

Professor of gynaecology at the Institute of Clinical Medicine, UiO and clinical consultant at OUS, Britt Ingjerd Nesheim, also sees no medical advantage to the introduction of early ultrasound:

"I think most women who have an early ultrasound do it because they want an indication of whether the child they are carrying may have Downs Syndrome. Whether we introduce routine early ultrasounds or not is therefore ultimately a question of values", says Nesheim. She notes that women have very individual reactions to finding out that their foetus has a chromosomal abnormality.

"The timing of this message might therefore not be all that important", Nesheim adds. "Whether the abnormality is detected in week 11 or week 18, the woman must make a difficult choice."

Important and difficult information

Information can be a burden. Yet the NOKC found research concluding that early ultrasounds could increase women's satisfaction with the prenatal care they received. During the Directorate of Health meeting on 16 January, Dagbladet journalist Anne Marte Blindheim told the story of her own choice to have an ultrasound in week 12, as she wanted to know that all was well with the foetus.This confirmation was part of the reason she experienced her pregnancy as positive.

"If I had been told that my child had a serious condition, I do not know what I would have done", Blindheim said.

"This is what many women say prior to having an ultrasound during their pregnancy", Staff confirms.

"We therefore face a considerable challenge in providing information to pregnant women. A 'normal' early or late ultrasound does not guarantee that the foetus is healthy, but rather shows that the examination did not uncover any pathology", Staff explains.

"For example, only 60 percent of all heart defects are discovered, even by talented investigators. There are no examinations today that can guarantee a healthy foetus, including when combined with amniotic fluid diagnosis, blood tests and the like", Staff notes.

Staff emphasises that whether to introduce early ultrasounds in the general prenatal care is a complex question, and that women's need for information differ.
"Norway is one of few European countries that does not systematically offer early ultrasounds. The introduction of ultrasounds in week 11-13 will provide a more equal system of prenatal care in Norway, but will also require a lot of information for pregnant women so that they understand what the examination may uncover."

Wants better adaptations

Staff believes that the debate around early ultrasounds also should focus on whether society is adapted for people living with disabilities.

"A country as wealthy as Norway should surely be able to look after all its inhabitants, including those born with disabilities or who become disabled. I find it strange that so many politicians in Norway focus on preventing a sorting society by not offering ultrasounds, at the same time as the municipalities do not provide sufficient support for families with disabled children. Whether or not early ultrasounds are introduced, adaptations for people living with disabilities should be prioritised", Staff concludes.

 

By Siv Tonje Håkensen