**2.3. Four-vessel umbilical cord**

Five percent of umbilical cords exhibit a four-vessel structure due to the persistence of small vitelline arteries, which follow the normal twisting of the main umbilical arteries. [28].

Four umbilical vessels view is an abnormal situation that has been reported to be associated with major congenital anomalies [29]. The presence of three umbilical arteries is the most common situation of four-vessel cord, although in the specialty literature have been reported a few cases of cord with two umbilical veins and two umbilical arteries [30].
