Endometriosis is a condition in which the endometrium, the tissue that normally the lines the uterus, grows outside the uterus. Like the endometrium, this tissue grows in response to monthly cycling hormones and sheds during menstruation. Since the shed fluid cannot easily exit the body, it can cause swelling and pain.
Growths can expand over time, forming scar tissue, causing adhesions (binding organs to each other), causing inflammation, and/or causing infertility by blocking fallopian tubes or growing over ovaries.
Most often endometriosis is found on the ovaries, but these growths can also be located on or in the Fallopian tubes, on the outside of the uterus, on ligaments that support the uterus, on the pelvic wall, intestines, bladder and ureters (tubes joining kidneys and bladder). Some women will experience pain with bowel movements or when urinating. Very rarely it can occur in the lungs, diaphragm, brain, or even the skin.
Up to 11% of women have endometriosis but, as about 25% of affected women have no symptoms, more may have the condition but remain undiagnosed. Almost half of sufferers have chronic pelvic or back pain, and up to half may experience infertility. Pain during sex is common, described as a “deep pain”. Seventy percent of women with endometriosis have pain during menstruation. The degree of pain does not necessarily correspond to the extent of endometriosis.
The cause or causes of endometriosis are not clear:
Family history increases risk, so researchers suspect an inherited component. Women who have a close family member with the condition may have six times greater risk of developing it.
Researchers also suspect a connection to environmental toxins with estrogen-like activity, and perhaps also a connection to decreased progesterone production (the natural hormone that balances or “opposes” estrogen reducing its effect).
"Retrograde menstruation”, where menstrual fluid flows in reverse out of the fallopian tubes and attaches to the outside of organs in the abdominal cavity, is the most accepted theory for the cause of this disease. However, this factor alone does not explain the cause, as many women can have retrograde menstruation but will not develop endometriosis.
Additional factors, such as genetic or immune differences need to be included to account for the fact that many women with retrograde menstruation do not have endometriosis.
Diagnosis
A health history and physical examination can lead to the suspicion of endometriosis, and ultrasound may identify the condition if large areas are present with associated cyst. However, laparoscopy (small incision surgery using cameras) is needed unless lesions are visible externally (for example in the vagina). A biopsy (removal of a small area of tissue for microscopic examination) confirms the disease.
Treatment
Pain medications
Non-prescription pain relievers in the NSAID family (non-steroidal anti-inflammatory drugs), such as ibuprofen and naproxen can help ease painful menstrual cramps. Naproxen sodium (rather than plain naproxen) is often preferred as it is absorbed more quickly, giving faster relief. NSAIDs also block prostaglandins, substances produced by the body that cause inflammation and promote cramping of the uterus, so they relieve cramps as well as pain. These medications should always be taken with food or milk to prevent stomach irritation.
Hormonal medications
Progesterone or synthetic progestins. Progesterone counteracts the actions of estrogen, and blocks the growth of both the endometrium and endometriosis tissue. Oral contraceptives and other forms of hormonal birth control, such as patches, vaginal rings and injections, contain progestin often along with estrogen and can have a favourable effect. Continuous cycle hormonal contraceptives are often preferred to decrease the frequency of menstruation with its accompanying pain.
Progestin-only birth control pills, IUDs (Mirena intrauterine device), implants or injections (Depo-Provera) can stop menstrual periods and reduce growth of areas of endometriosis. Usually, after a few cycles, periods will cease.
Regular estrogen/progestin birth control pills are also used, but add more estrogen to the woman's system which theoretically could oppose the beneficial blocking effect of the progestin on the endometriosis.
Gonadotropin-releasing hormone agonists (blockers), such as Lupron, block the menstrual cycle by preventing production of the hormones FSH and LH that stimulate the ovaries, resulting in stopping of periods altogether. They work well to shrink areas of endometriosis, but they effectively induce a chemical menopause with associated symptoms of hot flashes, vaginal dryness and bone loss. Periods return when the medication is stopped.
Danazol is another drug that blocks production of the hormones that stimulate the ovaries, preventing menstruation and symptoms of endometriosis. However, danazol is less preferred due to its side effects (male hormone-like effects: facial hair growth and voice changes) and potential to harm the baby, should a pregnancy occur.
Avoiding xenoestrogens (estrogen-like chemicals in the environment). Because these have a similar effect to our own estrogen, they can stimulate growth of endometriosis. Xenoestrogens are found in some pesticides, herbicides and plastics.
Aromatase inhibitors (drugs used to block formation of estrogen in women with estrogen related cancers) are being investigated for treating endometriosis.
Surgery
Areas of endometriosis are surgically removed as much as possible. Laparoscopy can be used for this surgery, allowing a faster recovery from surgery. Recurrence of endometriosis after surgery is up to 50% within 5 years, however, and adhesions (where pelvic organs become attached to each other) during healing are quite common.
A total hysterectomy (removal of the uterus, cervix and ovaries) is sometimes performed in women who do not wish to conceive, but areas of endometriosis also need to be removed to ensure pain does not persist. A partial hysterectomy (uterus only) is much less effective, as the ovaries continue to produce estrogen that would stimulate any remaining endometriosis causing pain. A hysterectomy is usually considered as a last resort treatment.
