Between the rectum and the bladder the peritoneum forms, in the male, a pouch, the rectovesical pouch (rectovesical excavation), the bottom of which is slightly below the level of the upper ends of the vesiculæ seminales—i. e., about 7.5 cm. from the orifice of the anus.
When the bladder is distended, the peritoneum is carried up with the expanded viscus so that a considerable part of the anterior surface of the latter lies directly against the abdominal wall without the intervention of peritoneal membrane (prevesical space of Retzius).
In the female the peritoneum is reflected from the rectum over the posterior vaginal fornix to the cervix and body of the uterus, forming the rectouterine pouch (rectouterine excavation; pouch of Douglas). It is continued over the intestinal surface and fundus of the uterus on to its vesical surface, which it covers as far as the junction of the body and cervix uteri, and then to the bladder, forming here a second, but shallower, pouch, the vesicouterine pouch (vesicouterine excavation). It is also reflected from the sides of the uterus to the lateral walls of the pelvis as two expanded folds, the broad ligaments of the uterus, in the free margin of each of which is the uterine tube.