Temporary change in menstrual cycles after COVID vaccine is common, study shows
BOSTON -- A new study confirms that some women will experience a temporary change in their menstrual cycles after receiving the COVID vaccine. Women had been reporting this side effect for some time.
Researchers at Washington University and the University of Illinois surveyed more than 39,000 currently and formally menstruating individuals between the ages of 18 and 80 who had been fully vaccinated against COVID-19. They found that 42 percent of people with regular menstrual cycles reported bleeding more heavily than usual after vaccination.
In addition, a significant percentage of people who did not typically menstruate, because they were on long-acting contraceptives, gender-affirming hormones, or are postmenopausal reported breakthrough bleeding.
However, experts say the changes in menstrual bleeding are temporary and not dangerous.