Single Umbilical Artery and Associated Fetal and Maternal Characteristics: A Cross Sectional Study

Background: Single umbilical artery is the most common developmental malformation of the umbilical cord. Its prevalence increases by multiple pregnancy, velamentous cord insertion, older maternal age, cigarrete smoking, maternal diabetes, hypertension or epilepsy. Since ethnic and genetic factors have been contributed to single umbilical artery occurrence and there is no similar study in Iran, we decided to evaluate fetuses with single umbilical artery diagnosis and describe maternal and fetal characteristics. Methods: This was a retrospective cross sectional study conducted on pregnant women having fetuses diagnosed with single umbilical artery at gestational age of 18 to 24 weeks referring to the perinatologist during 2019-2022. Data was analyzed by appropriate analytic tests were applied. Results: During study period, 67 fetuses had been diagnosed with single umbilical artery. Mean values of maternal age, gestational age, body mass index were 32.29 ± 5.83 years, 18.89 ± 1.57 weeks, and 26.46 ± 4.54 kg/m2, respectively. 59.7% of fetuses were male and 40.3% were female. 33 cases (49.2%) had no other associated malformations and choroidal cysts and intra-cardiac echogenic focies were the most prevalent abnormalities. As well, in 16 cases more than one malformation were detected. In cases with isolated single umbilical artery, no intrauterine growth retardation was evident. Conclusion: In line with previous studies, cardiac, gastrointestinal and renal malformation are the most common associated abnormalities seen in single umbilical artery malformation and in the presence of multiple anomalies intrauterine growth retardation is expected.