An investigation into the effects of COVID-19 vaccines on Iranian women’s menstrual cycle

ABSTRACT

Objective. The COVID-19 virus disrupts the renin-angiotensin system by reducing the expression of angiotensin-2 converting enzyme receptors in host cells, inducing an inflammatory response. This system regulates ovarian follicular development and ovarian steroid hormone production. So, this study has been conducted to examine the possible effects of COVID-19 vaccines on the menstrual cycle of Iranian women.
Materials and Methods. In this retrospective cohort study, an online researcher-made questionnaire containing 32 multiple-choice questions was used over one month to investigate the possible changes in the menstrual cycle after receiving COVID-19 vaccines among 916 eligible women aged 18 to 45 years.
Results. The mean age of participants was 34.34 ± 8.37 years, 77.79% were married, and 61.47% were government employees. The highest number of participants (n = 377, 39.68%) had been vaccinated with the Sinopharm. The most common menstrual disorder (n = 189) was menorrhagia. Most menstrual disorders were due to the AstraZeneca and Sinopharm vaccines. The chance of polymenorrhoea after receiving the Sputnik vaccine was 1.88 times higher than AstraZeneca (OR 1.88 and p = 0.04, 95%CI 1.02-3.46). The chance of hypermenorrhoea after the AstraZeneca vaccination was 2.77 times higher than after the Sputnik (OR 2.77 and p = 0.01, 95%CI 0.18-0.74).
Conclusions. Regardless of the type of vaccine, females subjected to COVID-19 may experience self-limiting menstrual abnormalities. Awareness of women before receiving the vaccine prevents further worries and uninformed judgments that negatively impact public attitudes.