Objective: To test the hypothesis that adolescent girls with menorrhagia rarely seek medical attention. Study design: A total of 705 adolescent girls attended a lecture on menorrhagia, completed an initial anonymous questionnaire, and were asked to participate in a more comprehensive study comprising a detailed bleeding questionnaire, a pictorial blood loss assessment chart, and blood tests. Results: A total of 105 adolescents (15%) reported they had heavy periods on the initial questionnaire. Among the 94 girls who completed the full questionnaire, 34 reported menorrhagia (36%; 95% CI, 26.5%-46.7%). Almost one-third (11 of 34) of these girls did not perceive having menorrhagia according to their response to the initial questionnaire. Menorrhagia was not related to age, years since menarche, or family history of menorrhagia. Among the 62 girls who consented to blood testing, 6 had anemia (9.6%; 95% CI, 3.6%-19.6%), all of whom had bleeding symptoms. Conclusion: Using standardized questionnaires, we were able to identify adolescents with menorrhagia associated with anemia. Importantly, some of these adolescents were not aware of having menorrhagia and/or anemia. Screening programs for menorrhagia in schools could result in better detection of menorrhagia among adolescents and consequent appropriate referral for medical consultation.