Which vessels lie posterior to the uterus and ovaries and supply the bladder, uterus, vagina, and rectum?

• A. Internal iliac arteries
• B. Ovarian arteries
• C. Uterine arteries
• D. Ovarian veins

Answer: (A)

The vessels described are the internal iliac arteries. In the pelvis, these arteries run posterolateral to the uterus and ovaries and give off branches that nourish the organs you mentioned: the bladder via the superior vesical arteries, the uterus and vagina via the uterine and vaginal arteries, and the rectum via the middle rectal arteries. This shared arterial source explains why a single vessel group is responsible for supplying all those pelvic structures. The ovarian arteries, which come off the aorta, mainly feed the ovaries (with some minor uterine branches) and are venous drainage through the ovarian veins, not the primary supply for the bladder or rectum. Uterine arteries do supply the uterus and part of the vagina, but the broader pelvic supply to bladder and rectum comes from the internal iliac system and its branches.