Transient Changes to the Menstrual Period in Women from Argentina Following Covid-19 Vaccination

Several vaccines against SARS-CoV-2 were developed in the last year and worldwide used to prevent further viral spreading. The main side effects caused by these vaccines include anaphylactic shock, pain at the administration site, fever, fatigue, myalgia, headache, and nausea. Although not listed as a side effect, period disturbance and vaginal bleeding have been reported repeatedly by women shortly after vaccination. We surveyed menstruating women who received at least one dose of any vaccine against SARS-CoV-2 used in Argentina during August 1 to September 8, 2021. Overall, 40% of the women who participated in the survey reported an alteration of their period. Disturbance in the menstrual period was more frequent in younger women. Menstrual cycle disturbances were manifested both with mRNA, viral vector, and inactivated virus-vaccines.