Prenatal ultrasound is the standard for the diagnosis of fetal anomalies. However, fetal MRI has emerged as a valuable diagnosis tool to complete the study of fetal malformations. Type II single umbilical artery results from the absence of both umbilical arteries and persistence of the vitelline artery. It has been described only in fetuses with sirenomelia or caudal regression syndrome. We report a favorable outcome in a normal fetus in which prenatal ultrasound and MRI showed a single umbilical artery arising from the aorta. The etiology of such a finding and its possible consequences are discussed.