Journal of Ultrasound in Medicine, Vol 19, Issue 9 619-623, Copyright © 2000 by American Institute of Ultrasound in Medicine
Prevalence of aneuploidy and additional anatomic abnormalities in fetuses with open spina bifida: population based study in Utah
C. J. Babcook, R. H. Ball and M. L. Feldkamp
Department of Radiology, University of Utah Health Sciences Center, Salt Lake City, USA.
Data were used to determine the population prevalence of aneuploidy and
additional anatomic abnormalities in fetuses with open spina bifida. The
ability of sonography to predict aneuploidy and identify additional
anatomic abnormalities in euploid fetuses was assessed. All cases of spina
bifida occurring in the state of Utah from 1995 through 1997 were reviewed
using Utah Birth Defect Network data, including stillborn, liveborn, and
terminated cases. Chromosomes were known in 45 of 51 cases of open spina
bifida. Of the 45 fetuses, 6 (13%) were aneuploid. Major anatomic
abnormalities were present in four of six (67%) cases, and two of six (33%)
cases had additional anomalies that could be missed sonographically. Of 39
euploid fetuses, 12 (31%) had additional abnormalities, but only half
likely would be detected sonographically. Our 4% risk of aneuploidy in
sonographically isolated spina bifida is substantially higher than the risk
associated with advanced maternal age (0.37%).
