Headache as a symptom of endometriosis externa

Prior to an abdominal operation, 125 patients were asked if they regularly had headache during the menstrual period together with or without pain in the lower pelvic region. Pelvic pain patients with endometriosis externa reported headache significantly more often than those without endometriosis. Headache proved to be almost as common a symptom as lower pelvic pain in patients with endometriosis.