Endometriosis is a condition limited to women. It involves the cells that grow inside the uterus that typically are released and passed each month with the menstrual cycle. But somehow those cells find their way outside of the uterus and implant in other areas in the abdomen and pelvis. Most commonly these might be either on the surface of the outside of the uterus on the tubes or ovaries or on the front or back surfaces of the pelvis. In more rare situations they actually implant on the surface of the bowel or even the bladder and sometimes and even more remote locations.