Menstrual Cycle Disorders after Covid-19 Vaccination

Abstract

Introduction. COVID-19 vaccines were developed one year after the official first case of COVID-19 in China was reported by the WHO. More than 3 billion doses have been administered so far. Menstrual disturbances have also been reported, primarily by women, and confirmed in scientific research. Aim. To evaluate menstrual cycle irregularities after COVID-19 vaccination among females in North Macedonia. Methods. A cross-sectional study was conducted that used a questionnaire to collect data in the period 03.2022-03.2023, including women aged 18-45 and residents of the Republic of North Macedonia. Women who were referred for an examination at the University Clinic for Gynecology and Obstetrics in the capitol of the country, were invited to participate in the survey. The questionnaire was distributed electronically. Results. A total of 191 women participated in this study, with a mean age of 34.318.05 years, 163 (85.3%) have been vaccinated, and 28 (14.7%) not vaccinated. Changes in menstrual cycle after COVID19 vaccination were found in 89 (46.6%), predominantly after their second dose. The most frequent menstrual cycle changes were: heavy periods/ bleeding (menorrhagia), infrequent/irregular periods (oligomenorrhea) and painful menstruation (dysmenorrhea). Disorders were noticed right after vaccination (at the first menstrual cycle) in 30(15.7%) women, and in 35(18.3%) the menstrual cycle normalized, while in 63(33.0%) the changes still lasted. Conclusion. In this study, an association of menstrual cycle changes and COVID-19 vaccination was found. More studies are needed and further follow-up in women with reported menstrual cycle changes.