Women were used as their own controls in the comparison of presterilization and poststerilization menstrual patterns. Five parameters were studied: regularity of cycle length, duration and amount of flow and incidence of dysmenorrhea and intermenstrual bleeding. Three parameters in the electrocoagulation group (regularity of cycle length and duration and amount of flow) and one parameter in the tubal ring group (duration of flow) showed significant changes after sterilization. However, by controlling for the effect of previous contraceptive methods used, no significant menstrual pattern changes following sterilization were discerned in either technique group.