umbilical arteries (changes after birth)
Last reviewed 06/2021
The umbilical arteries obliterate after birth. It occurs by two means:
- functional obliteration:
- occurs within a few minutes of birth
- due to:
- thrombosis in the lumen after ligating the umbilical cord
- mechanical stimuli at birth
- reduced oxygen tension through the vessel
- anatomical obliteration:
- takes several months
- due to fibrosis of the lumen by intimal proliferation
The only remnants of the umbilical arteries are fibrous cords in the adult; these are the medial umbilical ligaments which extend in the extra-peritoneal fat of the abdominal wall from the umbilicus to the superior vesical arteries. The latter remain patent.