Journal of Ultrasound in Medicine, Vol 19, Issue 3 201-205, Copyright © 2000 by American Institute of Ultrasound in Medicine
Foot length in fetuses with abnormal growth
N. B. Meirowitz, C. V. Ananth, J. C. Smulian, D. A. McLean, E. R. Guzman and A. M. Vintzileos
Department of Obstetrics, Gynecology, and Reproductive Sciences, UMDNJ-Robert Wood Johnson Medical School/St. Peter's University Hospital, New Brunswick, New Jersey 08903-0591, USA.
Sonographic fetal foot length is highly predictive of gestational age. In
order to assess the reliability of this parameter in predicting gestational
age in cases of abnormal fetal growth, we examined fetal foot length in
small- and large-for-gestational-age fetuses. A nomogram of foot length
versus gestational age between 15 and 37 weeks was constructed using
cross-sectional data obtained from 5372 singleton fetuses. Fetal foot
lengths for small-for-gestational-age fetuses (estimated fetal weight below
the 10th percentile) and large-for-gestational-age fetuses (above the
>90th percentile) fetuses were plotted against the foot length nomogram
in order to determine the number of small-for-gestational-age fetuses and
large-for-gestational-age fetuses with foot lengths below the 10th and
above the 90th percentiles, respectively. Of the 586
small-for-gestational-age fetuses, 355 (60.6%) had foot lengths below the
10th percentile on the nomogram. When foot lengths from
large-for-gestational-age fetuses were plotted on the foot length nomogram,
29.4% (219 of 744) had measurements above the 90th percentile. Fetal foot
length can be influenced by growth restriction as well as states of
accelerated fetal growth. Our findings imply that there are limitations to
the use of fetal foot length for gestational age assessment, particularly
in fetuses with growth abnormalities.
