Endometriosis is a disease affecting women that results in uterine lining tissue growing in places outside of the uterus, such as the fallopian tubes, ovaries, bladder, bowels, and even the lungs. The cause is unknown, but hereditary factors and the immune system may contribute. The mechanism of this abnormal growth, known as endometrial implants, is thought to be the result of backward flow of blood during menstruation. Once the lining implants on another surface, it undergoes thickening each month as a result of hormones from the ovary.
Hormones cause microscopic internal bleeding of the implants, which in turn causes an inflammatory response, tiny blood vessels to grow, and scar formation that is responsible for the clinical consequences of this disease. Whereas the lining of the uterus can be shed each month during menstruation, the endometriotic implants have nowhere to go.
The primary symptoms of endometriosis are abdominal or pelvic pain, excruciating periods, and pain during intercourse. The pain is described as cramping, but can be sharp, cause nausea and vomiting, or painful bowel movements. Some women have no symptoms at all. The condition is considered chronic and incurable, but both surgery and medication are helpful in relieving some of the symptoms. Depending on the location, endometriosis can cause infertility, and affected women have a higher risk of premature birth, miscarriage, placental abnormalities, small infants, and cesarean section.
Between 2% and 50% of women are believed to have 'silent' endometriosis, while 40-60% who experience abnormally painful periods have endometriosis. Infertility affects 20-30% of women with endometriosis, and approximately four per 1,000 women are hospitalized due to pain from this condition each year.
One theory for the cause of endometriosis is that tissue covering the inside of the abdomen and bowels, called coelomic epithelium and similar in origin to the uterine lining, turns into endometrial-type tissue in response to an unknown stimulus - which could explain the disease occurring in unusual parts of the body.
- Family history of endometriosis.
- Early age of menarche, or first occurrence of menstruation.
- Short menstrual cycles (less than 27 days).
- Long duration of menstrual flow (more than one week).
- Heavy bleeding during menses (period of discharge during menstruation).
- Defects in the uterus or fallopian tubes.
Signs and symptoms
About one third of women with endometriosis have no symptoms. When they do, they can include the following:
- Painful periods.
- Heavy or irregular bleeding.
- Pelvic pain.
- Lower abdominal or back pain.
- Painful sex.
- Pain with bowel movements.
- Bloating, nausea, and vomiting.
- Groin pain.
- Pain during urination and/or problems with urinary frequency.
- Pain during exercise.
- Medications that disrupt the monthly production of hormones are currently recommended and include gonadotropin-releasing hormone (GnRH) agonists, progestins, oral contraceptive pills, and androgens. The use of aromatase inhibitors is usually for refractory or recurrent endometriosis.
- Chinese herbal medicine (CHM) was found to be as useful - if not more effective - for endometriosis-associated symptoms after laparoscopy compared to danazol (androgen) and gestrinone. Oral and herbal enema preparations of CHM were used. Some types of pain such as rectal or lower back pain did not respond better to CHM though, but fewer side effects were seen in the CHM groups in one study.
- Continuous oral contraceptives that stop menses are as effective as injections of Lupron (a GnRH agonist), since both cause cessation equally well, according to a study done by Guzick et al.
- Medroxyprogesterone acetate or ProveraTM has proven effective for pain suppression in both the oral (10-20mg/day) and injectable preparations. Oral Megestrol acetate (another synthetic progestin) in doses of 40mg had similar good results.
- Danazol is a synthetic steroid that acts to reduce luteinizing hormone [LH] and follicle-stimulating hormone [FSH] production. By doing this, the ovaries do not produce estrogen and progesterone and the lining is suppressed.
- Letrozole (Femara), another treatment option, results in suppression of endometriosis.
- Surgery is the only guaranteed way to diagnose endometriosis and can prove helpful if removal of the implants is done at the same time. However, total eradication is impossible in most cases. Hysterectomy can offer the best chance for cure and improvement, for women who have already had children or do not wish to do so.
Endometriosis cannot be predicted or prevented, but it can be managed with variable outcomes. A high index of suspicion is needed, especially if young women and girls have trouble with periods, missing school or other activities as a result of pain and bleeding. Diagnosis can only be made by laparoscopy, but using oral contraceptives during this time might be the best chance to prevent progression and preserve fertility. The long-term safety profile of oral contraceptives has been established for those without any history of blood clots or other conditions that might predispose a patient to clotting.