Perinatal Management and Outcome of Fetuses with Single Umbilical Artery Diagnosed Prenatally.

> Objective: To investigate the perinatal management and outcome of fetuses diagnosed prenatally with single umbilical artery. Methods: Sixty-one consecutive fetuses with single umbilical artery diagnosed prenatally by ultrasonography were included. Thorough prenatal ultrasonographic screening was carried out to detect associated congenital anomalies. Chromosome study by either amniocentesis or cordocentesis was performed for all 61 of the fetuses with single umbilical artery. Thorough physical examination or autopsy was performed after delivery. Results: All 61 fetuses were confirmed to have single umbilical artery after delivery. Ten (16.4%) of the 61 fetuses with single umbilical artery had abnormal karyotypes. In the single umbilical artery group with abnormal karyotyping, 8 had detectable structural abnormalities, 1 had symmetrical intrauterine growth retardation, and 1 had no apparent congenital anomalies. For the 51 fetuses with normal karyotyping, 28 had abnormal ultrasonographic findings. In 23 fetuses with single umbilical artery without chromosomal or structural anomalies diagnosed in utero, 7 (30.4%) were found to have structural anomalies (3 with congenital heart disease, 3 with congenital renal disease, and 1 with limb deformity) after birth. Conclusion: Prenatal diagnosis of single umbilical artery should be made with caution to avoid false positive cases. When single umbilical artery is diagnosed prenatally, we suggest 1) targeted ultrasonography for detection of anomalies with cardiovascular, genitorenal, and limb-skeletal systems; 2) chromosome study for those with intrauterine growth retardation or other associated defects; and 3) thorough investigation after birth.