<prompt> Umbilical cord has?2 aery and 1 vein1 aery and 2 vein2 aery and 2 veinOnly one aery  <response>: A i.e. 2 aery and 1 veinInitially in embryo there are 4 vessels - 2 umbilical aeries 2 umbilical vein. The aeries carry venous blood from fetus to placenta veins carry oxygenated blood from placenta to embryo.At 4 months right umbilican vein disappears i.e. left umbilical vein is leftQ. So after 4 months umbilical cord contains 2 aeries left umbilical veinQA Single umbilical aery is present in 1 cases; more commonly in twins babies born to diabetic mothersQ. It is frequently associated with congenital malformation of fetus renal abnormalitiesQAfter bih left umbilical vein forms ligamentum teres hepatisQ ductus venosus form ligamentum venosum. 