development
Last reviewed 01/2018
Developmentally, the azygous venous system is derived from the:
- right posterior cardinal vein; its caudal section becomes a fibrous remnant which remains attached to the inferior vena cava, the rest forms the azygous vein
- left prevertebral venous plexuses; the left posterior cardinal vein degenerates, leaving the prevertebral plexuses to later form the hemiazygous system in the same position