The study will last approximately two weeks. Participants will be asked to monitor their medication doses and severity of bleeding during the course of the study. After the first visit, participants will be separated into two randomized groups and will receive either one tablet of oral contraceptive or a placebo twice daily, to be taken 12 hours apart at the same times each day. Participants will also receive platelet transfusions as needed to ensure that their platelet counts remain over 20,000/microliter. After seven days, researchers will assess participants' uterine bleeding and all participants will be given oral contraceptives in the second week of the study. Participants whose bleeding has decreased will receive only one tablet; participants who still have moderate to severe uterine bleeding will receive two tablets. A final assessment will be performed on day 14 of the study.