EMBRYOLOGY OF THE UMBILICAL CORD

• Derived from the stalk of the yolk sac and allantois.
• Forms between 5 and 12 weeks GA.
• The junction of the amnion and ventral surface of the embryo is the future umbilicus.
• The allantois arises as a diverticulum from the yolk sac, and extends from the early fetal bladder into the body stalk contributing to umbilical vessel development.
• Embryology of the umbilical vein.

	Umbilical cord at 10 weeks of gestation
Umbilical cord at 12 weeks of gestation	Umbilical cord at 13.5 weeks of gestation