The prevalence of menstrual changes in COVID-19 vaccinated women: A cross-sectional study.

Background: This study aimed to examine the prevalence of menstrual cycle changes (MCs) and their patterns among healthy Syrian women following the administration of the first and second doses of a vaccine.

Methods: A cross-sectional online survey following campaigns for COVID-19 vaccines was conducted in 2022 from June 26 to August 3. Data collected included the participants' demographic characteristics, vaccination status, and multiple-choice questions for MCs changes after the first and second doses.

Results: Of 236, 89.8 % completed all shots of the vaccine. After the first dose, 36.9 % reported MCs, and 35 % after the second dose. Most women did not experience changes in menstrual cycle frequency-81.8 % after the first dose and 83.4 % after the second dose. Similarly, most women did not observe changes in cycle length, or menstrual flow quantity-5.5 % after the first dose and 8 % after the second dose reported spotting. Dysmenorrhea was reported by 15.7 % and 14.1 % of women after the first and second doses, respectively.

Conclusion: MCs are a potential symptom that a healthy woman at childbearing age could have after a different type of COVID-19 vaccine. MCs patterns do not significantly differ following vaccine doses.