In medicine, the expression is used to refer to the recto-uterine pouch, also known as the Pouch of Douglas, the deepest point of the female peritoneal cavity.

The corresponding structure in women is the rectouterine pouch.

It is close to the rectouterine pouch.

The procedure of inserting the culdoscope into the rectouterine pouch is termed culdoscopy.

This back of the deep spot may be the so-called cul-de-sac, thought by some to be the rectouterine pouch, or another erogenous zone altogether.

The rectouterine pouch is used in the treatment of end-stage renal failure in patients who are treated by peritoneal dialysis.

Culdoscopy is a medical diagnostic procedure performed to examine the rectouterine pouch and pelvic viscera by the introduction of a culdoscope through the posterior vaginal wall.

In the balloon vaginoplasty technique, a foley catheter is laparoscopically inserted to the rectouterine pouch whereupon gradual traction and distension are applied to create a neovagina.

This area, in a human sexuality context, is sometimes referred to as the 'Deep spot' (in common with both the AFE zone and the Rectouterine pouch) or the 'Frisbee'.

The rectouterine pouch, being the lowest part of the peritoneal cavity in a woman at supine position, is a common site for the spread of pathology such as ascites, tumour, endometriosis, pus, etc.

One other theory is that it is the vesicouterine pouch, due to its proximity to the supposed location of the AFE zone and the supposed erogenous qualities of the rectouterine pouch.

More accurately, the name hints to a blind pouch or cavity in the female body that is closed at one end and, in a more specific sense, refers to the rectouterine pouch (or called the pouch of Douglas).

Implantation sites includes the peritoneum outside of the uterus, the rectouterine pouch (culdesac of Douglas), omentum, bowel and its mesentery, mesosalpinx, and the peritoneum of the pelvic wall and the abdominal wall.

In a sexual context, the rectouterine pouch is referred to as the epicenter, backstop or deep spot (in common with the AFE zone), the PFE zone (posterior fornix erogenous zone) or, most commonly, the cul-de-sac.

The word culdoscope (and culdoscopy) is derived from the phrase cul-de-sac, which in French literally means "bottom of a sac", here referring to a blind pouch or cavity in the female body that is closed at one end, that is the rectouterine pouch.