Am J Perinatol 1985; 2(3): 178-182
DOI: 10.1055/s-2007-999944
ORIGINAL ARTICLE

© 1985 by Thieme Medical Publishers, Inc.

Accurate Ultrasonic Estimation of Fetal Weight

William J. Ott, Sue Doyle, Sandy Flamm
  • Division of Maternal and Fetal Medicine, Department of Obstetrics and Gynecology, St. Louis University Medical School and St. Mary's Health Center, St. Louis, Missouri
Further Information

Publication History

Publication Date:
04 March 2008 (online)

ABSTRACT

The accuracy of eight ultrasonic fetal weight formulas were analyzed in 1099 fetuses who underwent real-time ultrasound examination within 72 hours prior to delivery. Shepard's formula was most consistently found to give the lowest systematic and random errors throughout all weight categories, though Deter's formula had an almost identical accuracy.

The Shepard formula was further analyzed in respect to the effects of fetal sex and birthweight centile grouping on the accuracy of fetal weight estimation. The results indicated that fetal sex had no effect on the accuracy of fetal weight estimation, but that birthweight centile grouping did. The weights of small-for-gestational age infants were systematically overestimated, while the weights of large-for-gestational age infants were systematically underestimated.