Sigmoidocele

Sigmoidocele (also known as pouch of Douglas descent) refers to a condition where the sigmoid colon descends (prolapses) into the lower pelvic cavity. This can obstruct the rectum and cause symptoms of obstructed defecation.

Pathophysiology
The phenomenon is caused by a weak section of fascial supports of the vagina (the uterosacral cardinal ligament complex and rectal vaginal septum), which allows a section of peritoneum containing the sigmoid colon to prolapse out of normal position and fall between the rectum and the vagina.

Diagnosis
It is not possible to differentiate between a rectocele and a sigmoidocele on vaginal examination. Defecating proctography will demonstrate a sigmoidocele during straining.

Epidemiology
Sigmoidocele normally occurs in females, and is uncommon.