In 2019, a Delphi panel was convened with experts in medicine, education, and public health. The panel, together with a systematic literature review of school-based menstrual health programs, informed the development of My Vital Cycles™ along with a questionnaire to test adolescent ovulatory-menstrual health literacy. In 2020, My Vital Cycles™ and the questionnaire were validated using focus groups, interviews and a test-retest. Adolescent girls, parents, teachers and school healthcare professionals were involved in this validation. My Vital Cycles™ is now trial ready.