Journal of Ultrasound in Medicine, Vol 16, Issue 4 241-249, Copyright © 1997 by American Institute of Ultrasound in Medicine
Improved birth weight table for neonates developed from gestations dated by early ultrasonography
P. M. Doubilet, C. B. Benson, A. S. Nadel and S. A. Ringer
Department of Radiology, Brigham & Women's Hospital, Boston, MA 02115, USA.
Most previously published tables of birth weight percentiles as a function
of gestational age have been derived from neonates with imprecise
gestational dating. In order to improve the accuracy of neonatal birth
weight percentiles, we developed a birth weight table based on measurements
from a group of neonates who had accurate gestational dating by prenatal
first trimester ultrasonography. By matching a database of obstetrical
ultrasonograms over a 5 year period to birth records at our institution,
3718 newborn infants with gestational dating by first trimester
ultrasonography were identified. Statistical smoothing and regression
techniques were applied to gestational age at birth and birth weight data
to develop a table for the 10th, 50th, 90th, and other weight percentiles
for 25 weeks of gestation onward. The weight table developed from our
population has lower 50th and 90th percentile weights, and narrower 10th to
90th percentile ranges, at 25 to 35 weeks than in prior tables. At 39 to 43
weeks, our 10th, 50th, and 90th percentile weights are higher than those in
previous tables. Our weight table for newborn infants, based on
measurements from neonates with accurate dating, permits improved
assignment of weight percentiles for gestational age and more accurate
diagnosis of growth disorders in fetuses and neonates.
