Two researchers are running a study to determine if there is any link between abnormal periods and the COVID-19 vaccine.
Dr Kathryn Clancy, an associate professor at the University of Illinois Urbana-Champaign, and Dr Katherine Lee, a post-doctoral scholar in the public health sciences division at the Washington University School of Medicine in St Louis, each received their shots earlier this year.
Both women noticed that aside from the usual side effects – such as a pain at the injection site – they also had temporary changes in their menstrual cycles.
Their periods had either come earlier usual, felt heavier or just appeared irregular.
Clancy and Lee are now collecting data on cycle changes post-vaccination to see if there is any association between the two.
Two researchers have launched a study asking women to document their menstrual cycle experiences after being vaccinated against COVID-19 (above)
As of Monday, more than 25,000 women have completed the questionnaire. Pictured: Ashley Dever, 20, a sophomore at Barry University, receives the first dose of the Pfizer COVID-19 vaccine at Jackson Memorial Hospital in Miami, April 15
Clancy first discussed her abnormal period in a tweet in late February after receiving the Moderna coronavirus vaccine.
‘I’m curious whether other menstruators have noticed changes too?’ she wrote.
‘I’m a week and a half out from dose 1 of Moderna, got my period maybe a day or so early, and am gushing like I’m in my 20s again.
‘I’m on day 3 of my period and am still swapping out extra long overnight pads a few times a day. Typical for me at this time is maybe one or two regular pads.’
The tweet was liked more than 1,200 times and she received hundreds of replies from other women and people who menstruate documenting their unusual changes.
The responses inspired Clancy and Lee to conduct a formal study.
On April 7, Clancy tweeted about the study and attached a link to a survey in which women could document their menstrual experiences after getting the jab.
‘Our survey was approved and made it through production! VACCINATED MENSTRUATORS ASSEMBLE,’ she wrote.
‘(This is a project to explore whether the covid vaxes affect the periods – if you have menstruated before and got the vax, take 15 min to tell us your experiences!)’
Lee told the Chicago Tribune that, as of Monday, more than 25,000 people have completed the survey.
The idea for the study came about after the women documented their own abnormal periods following vaccination on Twitter (above) and received hundreds of replies
‘Our survey cannot tell us anything about prevalence or the number of people who are affected,’ she said.
‘What we can do is look for associations and trends that help us direct whatever the next study would be.’
There is currently little to no research about how vaccines could affect periods, although some suggest that because immunizations stress the immune system, a person’s menstrual cycle could be responding to that.
Experts say none of the vaccines approved by the U.S. Food and Drug Administration – Pfizer-BioNTech, Moderna and Johnson & Johnson reported any changes to menstrual cycles during clinical trials.
They add that there is currently no danger in getting the COVID-19 vaccine and no reason to skip it.
Dr Mary Jane Minkin, a clinical professor in the Department of Obstetrics, Gynecology, and Reproductive Sciences at the Yale University School of Medicine, said there is no evidence linking the vaccine and abnormal periods.
‘Are there reports of funky periods? Yes. Do we have a ready explanation? I don’t think so,’ she told the Connecticut Post.
‘There’s no biological reason for it.’
Minkin said there are many reasons for irregular periods, such as stress, and that it is too early to suggest a link between temporary menstrual cycles changes and vaccinations.
She added that she hopes anecdotal reports do not dissuade women from being vaccinated against coronavirus.
‘If somebody’s got menstrual pain, we can take care of it,’ she said. ‘But we have a much harder time dealing with the COVID itself.’