Single umbilical artery. Prenatal detection of concurrent anomalies.

Prenatal sonographic findings were reviewed in 30 fetuses with a single umbilical artery (SUA) to determine the reliability of ultrasound for detecting concurrent anomalies. Additional anomalies were identified in 15 fetuses, including 3 fetuses with minor anomalies and 12 fetuses with major or multiple concurrent anomalies. Minor anomalies observed in 3 fetuses included 1 case each of pelvic kidney, unilateral absent kidney, and mild cerebral ventricular dilatation. Major abnormalities detected in 12 fetuses involved a variety of organ systems and included cardiac defects, holoprosencephaly, skeletal dysplasia, hydrocephalus, omphalocele, hydrothorax, enlarged cisterna magna, and diaphragmatic hernia. Clinical and pathologic correlation showed that all fetuses were correctly categorized regarding the presence of other anomalies; none of the 15 fetuses in whom an SUA was considered an isolated finding had a significant anomaly at birth. Chromosome abnormalities were found in 6 of 12 fetuses with major abnormalities but in none of the 18 remaining fetuses. We conclude that prenatal ultrasound can reliably identify major concurrent anomalies in fetuses with SUA. In the absence of additional anomalies, prenatal detection of SUA should not alter obstetric management.