Gastrointestinal involvement of endometriosis has been found in 6%-10% of reproductive age group women and exclusive localization on the ileum is very rare (1%-7%). Endometriosis is characterized by the presence of endometrial tissue consisting of glands and/or stroma
located outside the uterus. When the terminal ileum is affected by endometriosis, the entity distinction from other diseases of the ileocecal region is difficult in terms of clinical presentation, symptomatology and radiological appearance. Histological assessment after resection of the
involved small bowel segment in the three patients shows a final diagnosis of ileal endometriosis with confirmation by Immunohistochemistry which shows ER, PR and CD10 positive.