Endometriosis is a chronic, progressive disease among women of menstruating age. It occurs in up to 10% of these women and its incidence has markedly increased in the last several decades. The disease may result from the flow of menstrual blood up through the Fallopian tubes and into the lower abdomen and pelvis. This menstrual blood contains small amounts of the endometrial (inner) lining of the uterus and, in some women, the tissue implants into areas near the uterus, ovaries, bowels, bladder and connective tissue. Even though the endometriosis tissue is outside the uterus, it acts similar to normal endometrial tissue. During the first part of the menstrual cycle, the cells involved in endometriosis grow and multiply. During menstruation, the endometriosis tissue bleeds, resulting in inflammation of the pelvic area and considerable pain.
Chronic pelvic pain or pains in the back or legs are the most common symptoms, although some women may have no symptoms at all. There can also be extreme menstrual cramps, heavy vaginal bleeding, pain with urination or bowel movements, pain with sexual activity and, in many cases, infertility. In some cases, a woman can develop larger dark brown cysts in the pelvis that contain old blood that has built up over time. Scar tissue is not uncommon. If a woman has endometriosis on her ovaries, she may experience pain at the time of ovulation. Rectal bleeding occurs if she has deep lesions in the lower bowel. Because endometriosis cells make estrogen, a woman with endometriosis is almost always estrogen dominant (see estrogen dominance). Because of this, the menstrual cycle is often irregular, with spotting before one’s period and symptoms consistent with PMS. In severe cases of heavy bleeding, anemia can result.
The cause of endometriosis is basically unknown. Most researchers believe that the origin of endometriosis is what’s known as “retrograde menstruation” or the flow of blood backward from inside the uterus through the Fallopian tubes. Unfortunately, this occurs to a small degree every time a woman menstruates. What isn’t known is why some women get it and others don’t. The various theories include a defective immune system and the presence of excess estrogen that promotes the growth of endometriosis cells. The endometriosis cells make their own estrogen which creates a state of even greater estrogen dominance. The presence of xenohormones (hormones from outside the body) significantly contributes to the likelihood that a woman will develop endometriosis.