Endometriosis is a chronic, noncancerous disorder that may be painful. According to Merck, endometriosis is estimated to affect up to 15 percent of menstruating women between the ages of 25 and 44. However, the condition may affect teenagers and older women as well. Diagnosing the condition requires a surgical procedure, and therefore many cases may be going undiagnosed.
One of the main symptoms of severe endometriosis is pain in the lower part of the abdomen and in the pelvic region. The pain usually will worsen before and during a menstrual period.
Irregularities such as heavy menstrual bleeding and/or spotting may occur in women with endometriosis.
Some women with very little implants of misplaced endometrial tissue may have severe symptoms, including severe pain. Women with a large amount of implants may go years without any pain or other symptoms.
The implants could block the egg's passage leading from the ovaries into the uterus, causing infertility in severe cases of endometriosis. According to Merck, up to 50 percent of infertile women are diagnosed with endometriosis.
Other symptoms include pain during or after engaging in sexual intercourse and pain with bowel movements. Pain in any area of the abdomen, especially during or right before menstruation, is a warning sign of endometriosis.