The most inferior point in the pelvic cavity and common site for fluid collection is the rectouterine pouch.

• A. Rectouterine pouch
• B. Vesicouterine pouch
• C. Pararectal space
• D. Anterior cul-de-sac

Answer: (A)

In the pelvis, gravity pulls fluid to the deepest recess of the peritoneal cavity. The deepest space in females is the rectouterine pouch, located between the back of the uterus and the front of the rectum. Because of its position, it is the most dependent (lowest) point when a person is upright, making it the common site for free fluid to collect in the pelvis. The vesicouterine pouch sits anterior to the uterus between the bladder and uterus and is not as dependent. The pararectal space is lateral to the rectum, not the gravity-dependent lowest point. The anterior cul-de-sac refers to the vesicouterine pouch, not the deepest recess. So the rectouterine pouch is the correct and most likely site for fluid accumulation.