As COVID-19 vaccination expands across the United States, a small number of people have reported changes to their monthly menstrual cycles after receiving vaccine doses. While the relationship between COVID-19 vaccines and menstrual disruptions is unknown, the lack of information could lead to additional questions about the vaccine.
According to Alison Edelman, M.D., M.P.H., professor of obstetrics and gynecology in the Oregon Health & Science University School of Medicine, the effects of any vaccine, including but not limited to COVID-19, on menstrual cycles is not routinely monitored; however, the Centers for Disease Control and Prevention’s Vaccine Adverse Event Reporting System, or VAERS, for COVID-19 provides a unique opportunity to identify potential issues and concerns about the vaccine so they may be investigated further. The system recently proved valuable in gathering reassuring evidence that currently available COVID-19 vaccines are safe to take during pregnancy.
“We use menstrual cycles as an additional vital sign. While extreme disturbances can signal a medical issue, minor changes can also be worrisome especially if irregularities might cause an unnecessary pregnancy scare for some, or false hope about a potential pregnancy for others,” says Edelman. “Thus far, the few reports of menstrual changes following vaccination appear less extreme and temporary, which is unlikely to adversely affect someone’s health or wellness. However, the overall lack of knowledge limits health care providers’ ability to counsel and reassure people about what to expect, which may in turn, prevent individuals from getting vaccinated.”
With grant funding from the Eunice Kennedy Shriver National Institute of Child Health and Human Development (grant number NICHD- HD089957), a part of the National Institutes of Health, Edelman is leading a new study that will analyze period tracking data from several thousand individuals. The de-identified data -- collected by cycle tracking application Clue and FDA-cleared birth control app Natural Cycles -- will allow OHSU to study menstrual cycle characteristics specific to period length, timing, duration and volume during the pandemic.
Pre- and post- vaccination timeframes will be assessed, and compared to individuals who are unvaccinated. The team will also gather data about vaccine experience and menstrual cycle timing of the injection.
“We know that COVID-19 vaccines are safe and effective, and serve as the best protection against COVID-19 and severe disease,” says Edelman. “But we also know people want as much information as we can give them in order to help ensure ongoing confidence with the currently available vaccines. This research is one step in helping to provide this greater understanding.”
The Food and Drug Administration, the CDC, and the American College of Obstetricians and Gynecologists recommend that all eligible persons, including pregnant and lactating individuals, receive a COVID-19 vaccine or vaccine series.