Single Umbilical Artery in Fetal Autopsies: An Isolated Variant or a Marker of Multisystem Congenital Pathology?

Single umbilical artery (SUA) is one of the most common umbilical cord anomalies encountered during the prenatal and perinatal periods. Although isolated cases may follow a benign course, the presence of SUA has been reported to be associated with various structural congenital anomalies. The aim of this study was to determine the prevalence of SUA in a 10-year fetal autopsy cohort, to evaluate the association between the presence of SUA and congenital anomalies, and to demonstrate the risk it carries with regard to multisystem organ anomalies. A total of 641 fetal autopsies performed were retrospectively reviewed. Maternal age, gestational week, abortion/induction status, presence of SUA, and central nervous system, genitourinary system, gastrointestinal system, cardiac, pulmonary, musculoskeletal system, and multiple anomalies were recorded. Cases were classified according to umbilical cord structure into two groups: those with a single umbilical artery and those with a normal two-umbilical-artery configuration. SUA was detected in 35 (5.5%) of the 641 fetal autopsy cases. The rate of any congenital anomaly in cases with SUA was significantly higher than in cases with normal umbilical cord structure (p=0.0003). Multisystem congenital anomalies were observed significantly more frequently in the SUA group (p<0.0001). The presence of a single umbilical artery is associated with an increased risk of congenital anomalies in the fetal autopsy cohort and constitutes an important finding that warrants close attention. When SUA is detected prenatally, it should not be regarded solely as an umbilical cord anomaly; a detailed systemic examination should be performed for accompanying structural anomalies.