Through a prospective study the incidence and neonatal results of patients with persistent right umbilical vein are evaluated.

During the period between August 2009 and February 2011, 3,576 low-risk obstetric sonographies were performed by the same technician at four different centers of prenatal diagnosis. Persistent right umbilical vein was diagnosed during a customary ultrasound examination, in the abdominal transverse section used to measure abdominal perimeter. Patients were asked to bring their children several months after delivery for a clinical and sonographic evaluation.

Persistent right umbilical vein was found in nine fetuses. In one case, it was associated with single umbilical artery. All fetuses had good growth and development. In some children, the postnatal sonography showed the gallbladder toward the left of falciform ligament.

The incidence of persistent right umbilical vein in this population was of 1:397. We did not find any association with severe malformations as mentioned in the first articles related to this topic. There was only one case with single umbilical artery. All newborns developed normally. The question is raised why, being this anomaly so frequent and obvious, it is not more often diagnosed. Gallbladder position in respect to falciform ligament is a finding to assess.

Leal DB, Maggiolini M, Bianchi A. Prenatal Diagnosis and Postnatal Follow-up of Patients with Persistent Right Umbilical Vein. Donald School J Ultrasound Obstet Gynecol 2012;6(1):104-108.