American Journal of Roentgenology, Vol 157, 1275-1277, Copyright © 1991 by American Roentgen Ray Society
Sonographic prediction of gestational age: accuracy of second- and third-trimester fetal measurements
CB Benson and PM Doubilet
Department of Radiology, Harvard Medical School, Brigham and Women's Hospital, Boston, MA 02115.
We measured the accuracy of second- and third-trimester sonographic
predictors of gestational age against highly reliable gold standard
(crown-rump length) in a group of fetuses. Using a prospectively collected
computerized data base, we selected 460 fetal sonograms obtained at 14-42
weeks of gestation in which age could be reliably established on the basis
of crown-rump length in the first trimester. We used data obtained from
these sonograms to compare several predictors of fetal age. The accuracy of
all predictors worsened progressively as pregnancy proceeded. In the second
trimester, corrected biparietal diameter and head circumference were more
accurate predictors of gestational age than were biparietal diameter,
femoral length, and abdominal circumference (p less than .05, F test). In
the third trimester, the corrected biparietal diameter, head circumference,
and femoral length were the best predictors, significantly better than
biparietal diameter and abdominal circumference (p less than .05, F test).
Prediction of gestational age that relies on a single sonographic
measurement should be based on the head circumference or corrected
biparietal diameter in the second trimester and on one of these two
predictors or the femoral length in the third trimester.
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
