The endometrium is the inner lining of the uterus (the womb). During the menstrual cycle, this lining thickens as it prepares for the fertilized egg to implant. If an egg does not implant, the endometrium is shed, which you know as menstruation (having your period).
Endometriosis is a condition that occurs when endometrial tissue grows outside the uterus, usually around the ovaries, bowel, bladder, or lining of the pelvis. Endometriosis in other areas of the body is rare. The condition accounts for about 15 percent of female infertility
When endometriosis occurs, the displaced tissue continues to behave as usual, thickening and swelling in preparation for pregnancy and then breaking down. But the tissue has no way to leave the body. This can cause problems, such as inflammation, scarring, heavy periods, and pain. It can also lead to infertility.
It's not entirely clear what causes the endometrial lining to appear outside the uterus, or why endometriosis interferes with conception. It's possible that the inflammation and scarring that occur in the pelvis from endometriosis interfere with ovulation or block the passage of the sperm to the egg, but scientists aren't entirely sure.
Not all women who have endometriosis will have problems conceiving, but up to 50 percent will. For those women, treatments are available. The actual treatment recommended can vary from woman to woman, depending on the age of the woman, the severity of the endometriosis, and whether there are other things that may be causing infertility in addition to endometriosis. Sometimes, multiple factors are involved.
In some cases, a healthcare provider may recommend treating the endometriosis and then actively trying to conceive for a few months without treatment, since this may be enough to improve fertility. In other cases, a healthcare provider may recommend going straight to fertility treatment. If fertility treatment is used, it may include:
- Clomiphene citrate (Clomid®, Serophene®), a medication used to induce ovulation, with intrauterine insemination
- Gonadotropins to induce ovulation, with intrauterine insemination
- In vitro fertilization.