What is endometriosis and what causes it? Another great discussion question answered by The Lady Doctors:
Endometriosis (pronounced endo-me-tre-oh-sus) is quite common, about 1/10 women have it. But it is still not completely understood. Because of this, women don't know they have it. And even if they know something is wrong, the medical field has a hard time diagnosing and treating it. Ask anyone who has been diagnosed with endometriosis how many doctors they went to see before figuring out what was happening to their pelvic organs.
What is it? It is a condition where the tissue that lines the uterus, called the endometrium, grows outside of this normal location. When this tissue is in the lining of the uterus (remember this is normal), it responds to your monthly hormones, as it should. The lining builds up, you bleed it out. For a lot of us, this causes a lot of cramps during our periods. When this same tissue grows outside of the lining (like in your ovaries and tubes -- not normal) it becomes trapped and has no way to leave your body. All the while, this displaced tissue is responding to hormones and causing pain internally. For some women, the pain can be quite severe to a point that they cannot get out of bed. It's not just the small implants inside your pelvis and abdomen. Surrounding tissue inside the pelvis gets inflamed and this causes even more pain, scar tissue, cysts on the ovaries, and infertility.
What causes endometriosis?
Here's where we are not sure, but have a theory. We think that the blood that should be leaving your body during a period sometimes goes backwards into the tubes and then spills into the pelvis. This area inside your belly is where the tubes and ovaries and uterus are located. These small endometrial cells implant in the pelvis and cause scar tissue as well. None of us have control over this. There are other theories as well.
Another great resource to learn more about Endometriosis is the Endometriosis Foundation of America