“Impact of first trimester ultrasound on early detection of major fetal anomalies”, published in PLOS Medicine, is the first study to analyse national data linking first-trimester ultrasound protocols to detection rates for serious congenital anomalies.
Analysing more than 1 million pregnancies across England, the study found that NHS trusts using the most detailed early screening protocols detected 40% of major fetal anomalies before 16 weeks, compared with 28% in trusts with no formal anatomical assessment at this stage.
The findings have significant implications for national screening policy, parental decision-making, and equity of care. Despite technological advances making early detection possible, there is no national policy recommending first-trimester anatomical screening in England, leading to striking regional differences in practice.
Major findings
- Three-quarters of NHS trusts currently conduct first-trimester anatomical screenings, but what is assessed varies greatly.
- More detailed protocols were associated with substantially higher early detection rates for conditions such as spina bifida, major heart defects, and limb abnormalities.
- Some conditions (including acrania, exomphalos, and gastroschisis) were frequently detected early regardless of policy, while other conditions remained hard to detect before 16 weeks, even with detailed scanning.
Read the full story on the Nuffield Department of Women's & Reproductive Health website.