Combined first-trimester screening for preterm small-for-gestational-age infants: Australian multicenter clinical...

Area of Science:

• Maternal-fetal medicine
• Obstetrics and Gynecology
• Prenatal screening

Background:

• Small-for-gestational-age (SGA) fetuses delivered before 37 weeks pose significant risks.
• Effective first-trimester screening is crucial for timely intervention and improved pregnancy outcomes.
• The Fetal Medicine Foundation (FMF) developed a competing-risks model for predicting preterm SGA.

Purpose of the Study:

• To evaluate the performance of the FMF first-trimester screening model for predicting small-for-gestational-age (SGA) requiring delivery before 37 weeks' gestation.
• To assess the model's efficacy in a large Australian cohort.
• To explore the model's association with other adverse pregnancy outcomes.

Main Methods:

• Retrospective analysis of prospectively collected data from 22,841 women undergoing first-trimester screening.
• Comparison with a control group of 301,721 unscreened pregnancies in Victoria, Australia.
• The FMF model calculated risk for preterm SGA, but this information was not disclosed to patients or clinicians.

Main Results:

• The FMF model identified 13.3% of pregnancies as high risk for preterm SGA.
• Screening demonstrated a sensitivity of 48.6% and specificity of 87.0%.
• High-risk pregnancies were associated with increased rates of preterm pre-eclampsia and preterm birth; low-risk pregnancies had lower stillbirth rates.

Conclusions:

• Combined first-trimester screening for preterm SGA exhibits moderate efficacy.
• The FMF screening model can inform pregnancy management strategies.
• This approach may facilitate better antenatal resource allocation for high-risk pregnancies.