Prevalence of prenatal ultrasound diagnosed single umbilical artery in a cohort with associated congenital malformations

Abstract

Introduction: Single umbilical artery (SUA), a developmental abnormality of the umbilical cord occurs following primary agenesis or secondary atrophy of one of the arteries. It occurs in 0.08%–2% of pregnancies and associated with intrauterine growth restriction, preterm delivery, stillbirth, and congenital anomalies. Usually, the attending midwife or doctor determines the number of umbilical arteries at delivery. However, with the advent of prenatal ultrasound screening, the umbilical cord vessels can be determined as early as 14 weeks prenatally. The study aimed at determining the prevalence of SUA in University College Hospital (UCH), Nigeria, with associated anomaly (ies). Materials and Methods: This is a prospective cohort study of 989 fetuses who had detailed anomaly scan over 4 years at the ultrasound unit of the antenatal clinic, UCH. Results: Sixty-two fetuses had various anomalies, of which three had SUA, and these cohorts were followed up. The prevalence of SUA was 0.3% in both singleton and multiple gestations. Other anomalies detected with SUA include abnormal-shaped head, hypoplastic cerebellum, bilateral renal pyelectasis, bilateral ventriculomegaly, cavum septum defect, and ventricular septal defect. Conclusion: SUA is more common in twin gestations than in singletons, and if found in a fetus, it is a high risk for other anomalies which must be determined prenatally.