More worrisome is the fact that approximately 50% of endometriosis sufferers go undiagnosed and unaware of their condition, because they show no symptoms. Definitive diagnosis can only be made via surgery, which makes detection even more difficult.
Endometriosis is a condition where tissue similar to the lining of the uterus (the endometrium) is found elsewhere in the body.
In women suffering from endometriosis, bleeding occurs both inside and outside of the womb during menstruation.