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The COVID Vaccine Might Mess With Your Period


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With eligibility expanding, millions of people are getting the COVID vaccine every day, which is wonderful news. But getting the vaccine isn’t without side effects: sore arms, fatigue, temporary flu-like symptoms are all common side effects that you will be warned about or hear about from the vaccine. But one side effect that you may not be warned about and which is just now being discussed is that the COVID vaccine seems to have an effect on menstrual cycles.

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Speaking with Today, postdoctoral research scholar at Washington University School of Medicine Katharine Lee discussed how in conversation with other people who menstruate who received the vaccine, many reported that it had affected their cycle. But that evidence was only anecdotal, so after reaching out to one of her grad school professors, Kathryn Clancy, head of the Clancy Lab at the University of Illinois, they decided to gather more data. Clancy also experienced an abnormal period after her first shot of the vaccine and so she decided to put out the call for more information on social media to get a bigger sample size.

The survey is still ongoing, but Clancy and Lee hope that any information they receive will help them and the medical community better understand what sort of impacts the vaccine can have on periods. But just in this article there are reports of abnormally heavy periods, more intense period symptoms, and delayed periods.

“A lot of people had noticed something but hadn’t heard anything about (menstrual changes) being a side effect,” Lee today Today. “So many things could impact people’s menstrual experiences. So, we just thought if this is a side effect of … this type of vaccine it would be good for people to be prepared.” Some other studies show only a percentage of people who menstruate showing changes or abnormal periods, and it wasn’t noted as a side effect in clinical trials, but experts told Today that COVID does interact with estrogen in some way we may not understand and that could influence periods, as can other stressors on our systems.

On the one hand, it is comforting to know that other people are experiencing period irregularities due to the vaccine. I received my first dose last week and my period was predicted to start the next day and simply didn’t. Just knowing I’m not the only one who has experienced this is a relief.

But it is also frustrating that this wasn’t discussed or understood as a side effect and that how this vaccine affected the cycles of people who menstruate maybe wasn’t even considered. I feel as if to the vaccine developers, the bodies of people who menstruate or potential effects are outliers that don’t need to be accounted for. This same lack of consideration for the health of people who menstruate ties in with our discussion yesterday about how the Johnson and Johnson vaccine was paused due to potential blood clot issues when people using birth control have been asked to live with a much higher likelihood of blood clots for decades.

The takeaway here is that you should very much still get a vaccine as soon as you can to help end this pandemic, but if you menstruate, be aware that it could be affected, and if it is, fill out the survey so the people taking the time to study this have as much information as possible.

(via Today, Image: JOSEPH PREZIOSO/AFP via Getty Images)

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Jessica Mason
Jessica Mason (she/her) is a writer based in Portland, Oregon with a focus on fandom, queer representation, and amazing women in film and television. She's a trained lawyer and opera singer as well as a mom and author.

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