Endometriosis of the uterus - is a serious disease. It is worth considering if a dark brown discharge before menstruation are accompanied by:
soreness, aching in nature wearing abdomen. The degree of severity of the disease depends on the intensity of pain, gaining strength in the first day of menstruation;
pain in the pelvis, amplified before coming month, a little sagging after them and having softly pronounced in between periods;
allocation of endometriosis may have a different color, which obviously makes it clear that the body that something is wrong. In this case, menstrual discharge may be brown-brown, brown or even black.
The presence of these symptoms, most likely, is a symptom of endometriosis, but an accurate diagnosis is able to supply only specialist.