Non-invasive screening for fetal abnormalities in the first trimester of pregnancy is cost-effective for the NHS

Published on Wednesday, 05 February 2025 Post

A new joint study between researchers at Oxford Population Health's National Perinatal Epidemiology Unit, the Nuffield Department of Women's & Reproductive Health, and the University of Exeter Medical School has found that screening for eight major structural fetal anomalies during the routine ultrasound scan offered in the first trimester of pregnancy is likely to be cost-effective for the NHS. The study is published in BJOG: An International Journal of Obstetrics & Gynaecology.

In most high-income settings, including England and Wales, standard antenatal care includes at least two ultrasound scans: at 11–14 weeks of pregnancy to confirm fetal viability, establish due dates, and identify multiple pregnancies; and at 18–20 weeks to identify any major congenital anomalies that may affect the baby's development.

There have been calls to screen for some major congenital anomalies during the first trimester (up to 12 weeks) due to improvements in the quality of ultrasound images and to give parents more time for genetic testing, specialist support, and decision-making. Early detection may allow more time to prepare for the birth if the pregnancy continues, or if terminated, the procedure may carry fewer risks and less psychological distress than if performed during the second trimester. However, concerns exist that early screening could increase terminations, false positive findings, and detect anomalies that would have resolved later in pregnancy.

The ACCEPTS study assessed whether anomaly screening during the first trimester represents value for money for the NHS. Although the screening takes place during a routine antenatal appointment, additional time and resources would be needed. Screening at a population level is costly and healthcare services in the UK are under immense pressure. As offering additional screening at an earlier stage in pregnancy would result in increased costs for the NHS, it is important to consider the cost of the screening against the potential benefits.

To do this, the researchers developed a decision model that could predict the likely outcomes for mothers and infants, the cost of the current screening schedule over 20 years, and the cost of introducing a policy for additional screening during the first trimester. They also looked at the impact of additional screening on the predicted number of quality-adjusted life years (QALYs), or years in good health, for both the mother and infants to help determine whether the screening is cost-effective.

Key findings:

• Additional screening for anomalies during the first trimester of pregnancy increased average per-woman healthcare costs by £11;
• The model predicted that around half of parents who chose to terminate their pregnancy after a positive screening finding at 20 weeks would still make the same decision but now at an earlier stage, if they had received first trimester anomaly screening;
• Around 17% of the terminations predicted following first trimester anomaly screening were in parents who may have previously had their baby's condition diagnosed at 20 weeks and decided to continue with the pregnancy;
• Increased screening resulted in a predicted increase in QALYs for mothers and the model found that the cost of each QALY was within the limit of what the NHS considers to be cost-effective;
• As the additional screening would likely increase the number of terminations of pregnancies affected by an anomaly, the model predicted a decrease in infant healthcare costs and a reduction in the number of QALYs expected by infants.

Dr Helen Campbell, Health Economics Researcher at Oxford Population Health, said 'We recognise that first trimester anomaly screening raises complex, challenging and sensitive issues. It has implications for both mothers and infants and through this comprehensive modelling we have quantified these for the first time. We hope that this work will provide a meaningful contribution to the policy debate around whether to implement first trimester anomaly screening in England and Wales.'