A second vestigial umbilical vein : a case report

Malta Medical Journal Volume 21 Issue 01 March 2009 Abstract A healthy female infant was found to have two umbilical arteries and two umbilical veins at the cut surface of the cord at birth. Detailed inspection of the cord showed the second vein to represent a short segment vestigial vessel that, moreover, was not associated with any other congenital anomaly as is often found in infants with umbilical vein anomalies. Introduction The primitive umbilical cord starts to develop at around 12 days after implantation, forms a connecting stalk by 20 days and, by 5 weeks, contains the yolk sac stalk (vitelline duct), allantois remnant and umbilical vessels including two arteries and a vein. By 10 weeks the vitelline duct disappears and, by 3 months all barring the umbilical vessels and Wharton’s jelly remain. Initially, two umbilical veins originate in the chorionic villi from where they carry oxygenated blood to the embryo. They first connect with the hepatic venous plexus but, by the 6th week in utero, the proximal segment of the left vein and the entire right vein involute, leaving the left vein as the only venous contact with the placenta.1