Associated anomalies and perinatal outcome in fetuses with prenatally diagnosed single umbilical artery

Park, Mi Hye; Oh, Kwan Young; Yang, Yun Seok; Hwang, In Taek; Park, Joon Suk

Abstract

OBJECTIVE
To evaluate pattern of associated structural anomalies, abnormal karyotypes and perinatal outcomes of fetuses with prenatally diagnosed single umbilical artery and to evaluate the relation of absent side of a single umbilical artery in association with anomalies and abnormal karyotypes.
MATERIALS AND METHODS
30 fetuses with a single umbilical artery were detected by prenatal ultrasound examnination between March 1998 and June 2001 at Eul-Ji University Hospital. All medical records were reviewed for maternal demographics, associated anomalies, karyotypic analysis, pregnancy complications, and neonatal outcome.
RESULTS
Of the 30 fetuses, 11 (36.7%) were terminated because of severe anomalies and 2 (6.7%) experienced neonatal death. 17 fetuses (56.7%) had an associated structural anomaly. The structural anomalies found in association with single umbilical artery were cardiovascularac system (9 cases, 30.0%), urogenital system (6 cases, 20.0%), central nervous system (5 case, 16.7%) and ectopia cordis (1 case, 5.9%) and 7 cases (20%) among these had multiple malformations. Karyotype analysis was availabe in 25 cases and 5 (20%) of these were chromosomally abnormal. All of the karyotypically abnormal fetuses had a structural defect diagnosed on prenatal ultrasound examination in addition to the single umbilical artery. Of 13 fetuses without any associated structural or chromosomal anomalies, 3 (23.1%) demonstrated growth restriction. Of the 26 cases identified the absent side of a single umbilical artery, the right umbilical artery was absent in 13 (50%) and the left in 13 (50%) fetuses. The frequency with associated structural and chromosomal anomalies was equal on right (53.8%; 15.4%) and left (69.2%; 15.4%) sides.
CONCLUSION
Scanning the umbilical cord should be one of the essential parts of 2 nd trimester ultrasonographic examination. When single umbilical artery is detected, a detailed ultrasonographic examnination including fetal echocardiography and fetal karyotyping should be recommended for search of associated structural and chromosomal abnormalities. In cases where single umbilical artery is an isolated finding on prenatal ultrasound, careful attention to fetal growth is necessary.