LAUSR

Description COVID-19 vaccination causes small changes to menstruation that quickly resolve The rapid development of safe and effective vaccines against COVID-19 has been a triumph of medical science, but vaccines only work if people take them. Although there is extensive evidence that COVID-19 vaccination does not affect fertility, misinformation that it could has been a major source of vaccine hesitancy among young women. As the vaccination program was rolled out to younger age groups, some people noticed menstrual changes after COVID-19 vaccination, and many members of the public found these reports concerning. Research was needed to generate robust data to inform health care professionals and the public about these potential side effects. Menstrual changes have been reported in association with a variety of vaccines, including those against pathogens other than severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), so a secondary aim of this work is to understand the mechanisms by which vaccine-associated menstrual changes could occur.