The pararectal fossa (or pararectal pouch) is an inferior-ward extension of the peritoneum on either side of the rectum.

It is formed by a (sacrogenital) fold of peritoneum extending inferior-ward from the posterolateral pelvic wall.

[1] It varies in size with the distension of the rectum.

[citation needed] In females, the pararectal fossae often represent the inferior-most portion of the peritoneal cavity (sometimes, the inferior-most portion is instead rectouterine pouch).

[2] This article incorporates text in the public domain from page 1154 of the 20th edition of Gray's Anatomy (1918)