Pouch, rectovaginal: An extension of the peritoneal cavity between the rectum and back wall of the uterus.
The term "cul-de-sac," aside from being any "blind pouch or cavity that is closed at one end," is used specifically to refer to the rectouterine pouch. From that fact comes:
- Culdoscopy, the introduction of an endoscope through the vagina into the cul-de-sac;
- Culdoscope, the viewing tube (endoscope) that is used to look into the cul-de-sac; and
- Culdocentesis, the aspiration (withdrawal) of fluid from the cul-de-sac.
In French, "cul-de-sac" literally is "bottom of (a) sack." As early as the 13th century, a cul-de-sac was a dead-end street (or a dead-end way), a blind alley. (The third letter in "cul" is silent in French; in English it is spoken. So, in French "cul" is pronounced "ku" and in English "kul").
The rectouterine pouch is also known as excavatio recto-uterina (literally, the rectouterine excavation) and the pouch of Douglas, after the Scottish anatomist James Douglas (1675-1742) who explored this region of the female body and left his name attached to at least 3 other structural features of the area.