Using Down syndrome serum screening results to predict low birthweight

Area of Science:

• Maternal-fetal medicine
• Biochemical screening
• Perinatal epidemiology

Background:

• Prenatal screening for Down syndrome is routine.
• Predicting low birthweight (LBW) and very low birthweight (VLBW) is crucial for infant outcomes.
• Current methods for LBW prediction have limitations.

Purpose of the Study:

• To evaluate the utility of Down syndrome prenatal screening markers for predicting LBW (<2500 g) and VLBW (<1500 g).
• To determine the predictive accuracy of single and multiple serum markers, maternal weight, and smoking status for LBW and VLBW.

Main Methods:

• A retrospective record linkage study was conducted.
• Maternal serum screening results were linked with birth records for 42,259 pregnancies.
• Statistical analysis assessed the predictive performance of various markers and clinical factors.

Main Results:

• Single markers like alpha-fetoprotein (AFP) and human chorionic gonadotropin (hCG) showed associations with LBW.
• A combination of multiple markers (AFP, unconjugated estriol, inhibin A) with maternal weight and smoking adjustment yielded the best prediction.
• This multi-marker approach achieved a 5% false-positive rate, predicting 23% of LBW and 39% of VLBW infants.

Conclusions:

• Down syndrome screening markers can be repurposed for LBW prediction with minimal additional cost.
• This predictive capability can inform decisions on delivery location and identify candidates for LBW prevention trials.