The lifeline of the growing fetus (foetus)
Attaches to the umbilicus (duh) in the fetus and to the foetal surface of the placenta in the uterus. Usually about 50cm long and about 2cm in diameter. It contains two umbilical arteries and one umbilical vein, buried within Wharton's jelly. For the potential embryologists out there, it also has remnants of the yolk sac and allantois.