Primary dysmenorrhea is menstrual pain that is not associated with pelvis pathology. It usually begins with the onset of ovulatory cycles, characteristically appearing in the year after menarche and increasing with time. The pain is associated with increased myometrial activity. Oral contraceptives and prostaglandin synthetase inhibitors are effective in alleviating symptoms. Causes of secondary dysmenorrhea, such as pelvic inflammatory disease, endometriosis and uterine myomas, must be excluded before treatment is given.