Endometriosis of the intestine and genitourinary tract.

As with other organs, the etiology of bowel endometriosis is unknown. Its occurrence was reported as early as 1922 by Sampson. Following his investigation of nineteen cases, he proposed that "implantation adenoma of endometrial type of some portion of the intestinal tract may be present in at least one half of the cases of perforated ovarian hematoma of endometrial type with peritoneal implantations."