- Females of childbearing age who had not used or did not plan to use acceptable birth control measures, for the 12 months duration of the study. Oral, injected or implanted hormonal contraceptive, diaphragm, condom, intrauterine device or sexual abstinence were considered acceptable forms of birth control. If sexually active the subject must have been using one of the accepted birth control methods for at least 30 days prior to study entry;