Endometriosis
Endometriosis is a condition in which tissue similar to the lining of the uterus (womb), grows in locations outside the uterus. It irritates the nerve endings of these organs, and interferes with normal functions, causing (often severe) pelvic pain, irregular menstrual bleeding, infertility and sometimes bowel and bladder symptoms. Because it tends to mimic other pelvic, bowel and bladder conditions, endometriosis can take months, or even years, to be diagnosed and properly treated.
Endometriosis Association of Victoria (Australia)