Pain associated with endometriosis (chocolate cyst) typically presents as menstrual cramps. These pains usually begin just before menstruation and continue throughout the menstrual period. Patients may complain of pain concentrated especially in the pelvic area, radiating to the legs and lower back. Endometriosis can also cause pain during sexual intercourse (dyspareunia). In some cases, pain may also be encountered in the intestines or bladder.