Sonographic recognition of major malformations and aberrant fetal growth in trisomic fetuses.

Structural malformations and growth retardation are commonly observed in chromosomally abnormal newborns. This study assesses the sensitivity of ultrasound for detecting aberrant fetal growth patterns and chromosome-related major malformations. The study population consisted of 74 trisomic fetuses (trisomy 13, 9; trisomy 18, 22; trisomy 21, 43). Overall, 63% (38 of 60) of trisomic fetuses had at least one major malformation on postnatal examination. One or more major anomalies were identified by prenatal sonography in 68% (26 of 38) of these malformed fetuses and 43% (26 of 60) of the entire trisomic population. Midtrimester onset growth retardation was evident in 43% of fetuses with trisomy 13 and 59% of fetuses with trisomy 18. These findings suggest that a systematic fetal anatomic survey can be a powerful screening tool for the prenatal detection of chromosome abnormalities.