Q:   What causes endometriosis?
A:   The most widely accepted cause of the disease is retrograde menstruation. That means tissue from the uterine lining, called endometrial tissue, flows backward through a woman's fallopian tubes while she is menstruating. The tissue gets trapped and can't leave the body the way the rest of the endometrial lining does during menstruation. However, no matter where it is in the body, endometrial tissue still responds to hormonal stimulation each month. Endometriosis implants can become inflamed, bleed, and develop into scar tissue. When the implants are attached to organs in the pelvic and abdominal cavities severe pain, infertility and other problems may result. There are other theories about what causes endometriosis, including a deficient immune system response, hormonal imbalances or environmental causes. Experts also have found strong evidence to suggest a genetic link to the disease.

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