Neonatal Outcomes in Fetuses With a Persistent Intrahepatic Right Umbilical Vein

Objectives A fetal persistent intrahepatic right umbilical vein has been linked to anomalies and genetic disorders but can be a normal variant. We conducted a retrospective review to determine other sonographic findings that can stratify fetuses for further evaluation. Methods A total of 313 fetuses had a persistent intrahepatic right umbilical vein identified on 17- to 24-week sonography. The outcome was any major congenital anomaly or an adverse neonatal outcome, which was defined as aneuploidy, fetal demise, or neonatal death. Results A total of 217 patients (69.3%) had a normal neonatal outcome. Sixty-nine patients (22.0%) were lost to follow-up. Five fetuses (2.1%) had aneuploidy; 4 of the 5 had additional sonographic findings, and 1 had an isolated persistent intrahepatic right umbilical vein. Twenty-four fetuses had a major anomaly in association with the persistent right umbilical vein; 26 additional fetuses had soft sonographic markers associated with karyotypic abnormalities but were chromosomally normal. Of those with adverse neonatal outcomes, 12 had a congenital heart defect (57%). An additional sonographic finding with a persistent intrahepatic right umbilical vein was predictive of a congenital anomaly or an adverse neonatal outcome (P < .001), with a positive predictive value of 44.0% (95% confidence interval, 30.0%–58.7%). An isolated persistent intrahepatic right umbilical vein had a 0.4% risk for a congenital anomaly or an adverse neonatal outcome. Conclusions A persistent intrahepatic right umbilical vein should prompt an extended anatomic survey and a fetal cardiac evaluation. If the survey and cardiac anatomy are reassuring, no further follow-up is needed. If additional findings are identified, genetic counseling and invasive testing should be considered.