['The purpose of this study was to determine if a breast self-examination (BSE) "prompt" on oral contraceptive pill (OCP) packages would improve the frequency and timing of BSE among women who use OCPs.', 'Women between 13 and 40 years of age who were initiating, restarting, or continuing use of OCPs completed a baseline survey that assessed health behavior and practices. All received BSE education, and then were randomized to take either OCPs with a BSE prompt or regularly packaged OCPs (without BSE prompt) for three cycles. Three months later, subjects completed a follow-up survey that assessed BSE frequency and timing. A telephone survey of randomly selected subjects conducted 6 months after the baseline survey assessed BSE compliance after discontinuation of the prompt.', 'Of the 907 subjects at baseline, 49.3% performed BSE monthly but only 24.5% performed BSE during the correct time of the menstrual cycle. Among subjects who never performed BSE prior to the study, 40.3% of prompt subjects and 36.4% of the education-only subjects began BSE by the 3-month survey. Among subjects who performed BSE less than once per month at baseline, 50.9% of prompt subjects and 45.5% of education-only subjects increased the frequency of BSEs to a monthly basis by the 3-month survey. More women performed BSE during the correct time of the menstrual cycle at the 3 month follow-up survey (68.1% prompt, 62.2% education only) and 6-month survey (57.4% prompt, 48.9% education only) when compared with the baseline survey (24.7% prompt, 24.1% education only). Ninety-one percent of women in this study expressed a preference for a BSE prompt on OCP packaging.'] Does effectiveness of breast self-examination prompt on oral contraceptive packaging?