Middle rectal veins

The middle rectal veins (or middle hemorrhoidal vein) take origin in the hemorrhoidal plexus and receive tributaries from the bladder, prostate, and seminal vesicle.

Middle rectal veins
Scheme of the anastomosis of the veins of the rectum
Details
Drains from	Rectum
Drains to	Internal iliac vein
Artery	Middle rectal artery
Identifiers
Latin	venae rectales mediae
TA98	A12.3.10.018
TA2	5030
FMA	70912
Anatomical terminology [edit on Wikidata]

They run lateralward on the pelvic surface of the levator ani to end in the internal iliac vein. Veins superior to the middle rectal vein in the colon and rectum drain via the portal system to the liver. Veins inferior, and including, the middle rectal vein drain into systemic circulation and are returned to the heart, bypassing the liver.^[1]