Ultrasonographic prediction of neonatal survival in extremely low-birth-weight infants.

Abstract

Our purpose was to improve the accuracy of prenatal prognostication by directly correlating obstetric ultrasonographic measurements with neonatal survival. We studied 130 singleton live-born infants with birth weights between 500 and 1000 gm and who underwent complete ultrasonographic examinations within 3 days of delivery. Ultrasonographic measurements were evaluated as screening tests for neonatal survival by means of receiver-operator characteristic curves and compared with birth weight and pediatric assessment of gestational age. Eighty infants survived, and 50 died. Visual inspection of the receiver-operator characteristic curves indicated that biparietal diameter was the best predictor of survival. While correctly identifying all survivors, biparietal diameter predicted nonsurvivors better (p < 0.0001) than did actual birth weight or any other variable. Our findings indicate that using biparietal diameter to determine neonatal prognosis is significantly more reliable than the current practice of using estimated fetal weight. We speculate that biparietal diameter may reflect maturity more accurately because it is less subject to variation in growth.