Fetal weight estimation in twin pregnancies

Abstract In this study the fetal weight was estimated by ultrasound measurements of the biparietal (BPD) and abdominal diameters (AD) in 154 consecutive twin pregnancies. In 80 twins an attempt to estimate fetal weight was made 0–4 days before delivery (26% of all twins examined). In 84% (67 infants) it was possible to estimate the fetal weight using the formula (0.0108 × AD 1.72 × BPD 0.99 ). 60% of the birth weights deviated less than 10% from the estimated fetal weight and 83% deviated less than 15%. The prediction error was nearly constant, expressed as percent of actual weight in the different weight groups (8.5–9.8%). In 19 LGA infants, 69% of the birth weights deviated less than 10% from the estimated fetal weight and 70% deviated less than 15%.