Endometriosis describes the presence of normal endometrial tissue (the uterine lining) outside of the uterus. Usually this tissue stays in the pelvis, but in some cases it can be found outside the pelvic cavity. The actual incidence of endometriosis is uncertain, but it is estimated at two to five percent of the general female population. There is a familial predisposition, and women who have a mother or sister with endometriosis have as much as tenfold increased risk of getting it themselves.
The most common symptoms of endometriosis are: significant pain around menstrual flow; painful intercourse; difficulty getting pregnant. There are a number of theories about why endometriosis occurs, but the most commonly accepted explanation is called “retrograde menstruation.” In this theory, menstrual flow not only comes down through the cervix and out the vagina during the menstrual period as it is supposed to do, but also goes the opposite direction-up through the fallopian tubes and out into the pelvis. Some of the fragments of endometrial lining implant on the surface of pelvic organs such as the ovaries, bladder, or external surface of the fallopian tubes and continue to grow, resulting in endometriosis. As one of my patients said, “It’s when the lining of the uterus grows in the wrong place.”
These abnormally placed endometrial fragments respond to the hormonal cycle just like the normal endometrium inside the uterus. Because of this, endometriosis and normal endometrium undergo similar growth and bleeding phases during the cycle. The body’s defenses recognize the presence of endometriosis as abnormal and attack the tissue, resulting in local inflammation and scarring. Because the endometriosis is usually on or close to the ovaries and fallopian tubes, it is thought that the inflammation can interfere with the ability of the sperm to fertilize the egg, but more research is necessary. In more severe cases, the inflammation and scarring can damage reproductive organs, or the scar tissue can envelop the ovaries or tubes, effectively forming a barrier between the sperm and egg.
Treatment for Endometriosis
Endometriosis is a chronic disorder. Even if you treat endometriosis with surgery, removing all visible signs, it will return in the future. If you have been diagnosed with endometriosis through surgery, or if your physician suspects endometriosis but thinks surgery is unnecessary, you do have medical options that are very helpful in minimizing the effects of the endometriosis to allow you to maximally preserve you fertility. To maximize your chances to conceive naturally, you should consider the use of suppressive hormonal medications until you are ready to get pregnant.
The most common recommendation for suppression of chronic endometriosis, especially in patients who wish to preserve their fertility, is to start oral contraceptives. Estrogen is the main stimulus in the growth of endometriosis, whereas progesterone is the main inhibitor of growth. The overall effect of the oral contraceptive is progesterone-like. Progesterone-like effects make the normal endometrium in the uterus thinner and should also make the endometriosis shrink.
Additionally, some researchers believe there is less chance of retrograde menstruation, which would further spread the endometriosis. Other effective chronic treatments include Depo-Provera (Upjohn), an intramuscular injection of medroxyprogesterone acetate-again, a progesterone-like medication-every twelve weeks, or daily oral therapy with medroxyprogesterone acetate or other progesterone-like oral medications.
Gonadotropin-releasing hormone agonists, the most common being luprolide acetate, or Lupron, can be a very effective short-term treatment of endometriosis, because they effectively shut down nearly all estrogen production. The short-term side effects are the same as those associated with menopause (for example, hot flashes), and these medications also provoke the unfavorable long-term side effects of menopause, notably bone-density loss (osteoporosis).
For these reasons gonadotropins-releasing hormone agonists are commonly not employed for more than three to six months, so they are not useful for chronic endometriosis.
Danocrine (Danazol) would be another option, but side effects such as acne, oily skin, unwanted hair growth, weight gain, water retention, and adverse cholesterol changes have made it less popular and rarely used. The latest advances in medical therapy are aromatase inhibitors, but more research is necessary.
Laparoscopic surgery is commonly needed to either diagnose or treat endometriosis. Unfortunately, MRI, CT, or ultrasound cannot usually detect endometriosis.
Dr. Williams is actively involved in endometriosis research, in particular surgical techniques involved in removal of endometriomas-cystic growths of endometriosis in the organs.