Clinical estimate of birth-weight in labour: factors influencing its accuracy

Clinical assessments of birth-weight were made among 88 parturients at term, to determine what maternal and neonatal factors influence the accuracy of predicting neonatal weight. An estimate within +/- 10% of actual weight was considered accurate, while a prediction off by more than 10% was classified as inaccurate. Seventy-one per cent (63 of 88) of the estimates were considered accurate and 28% (25 of 88) inaccurate. Among these 2 groups of patients, univariate analysis did not identify maternal age, gravidity, parity, gestational age, maternal height, prepregnancy weight and maternal body mass index, maternal weight and maternal body mass index at the time of delivery, change in body mass index during pregnancy, intrapartum amniotic fluid index, newborn's weight, length, and ponderal index as being significant correlates of an accurate clinical estimate of the birth-weight. Over 2 years, as the provider gained experience in predicting the neonatal weight, the accuracy of the clinical estimate of birth-weight did not improve.