An accurate method for sonographic estimation of the weight of very preterm fetuses

This study was undertaken to test the accuracy of formulas we recently developed for the sonographic estimation of the weight of very preterm fetuses. The formulas were used to determine estimated weights from prenatal sonographic data for 62 premature infants born at 23-29 weeks of gestation, weight < or = 1,400 g. The mean absolute deviation of the actual birth weight from the estimated weight was 75.8 +/- (SD) 68.5 g, the mean percent deviation +0.60% and the absolute mean percent deviation 8.1 +/- (SD) 5.6%; 90.3% of the birth weights lay within 15% of the estimated weight. The model described represents an accurate method for prenatal estimation of the weight of very preterm fetuses.