When people started taking the Covid-19 vaccine last spring, some noticed unexpected side effects – their periods were heavier, started earlier or were longer.
Researchers Kathryn Lee, PhD, and Kathryn Clancy, PhD, started a survey to capture people’s post-vaccination experiences after they happened to hear that their periods had changed. The results were published in the journal Science Advances The covid-19 vaccine changes menstruation For some.
“It’s definitely happening,” said Lee, an assistant professor in Tulane University’s anthropology department and co-author of the paper. “It has now been confirmed by other groups using prospective approaches.”
Doctors believe this information can help them advise patients on the Covid-19 vaccine.
“It’s incredibly important to make sure people are prepared and not surprised. If you go and get the vaccine and they don’t tell you you have a fever the next day, it’s very concerning because you didn’t expect it,” Lee said. “At least people aren’t surprised to know that menstrual bleeding changes can happen. They didn’t panic. They don’t worry that something big has gone wrong.”
A A recent study It has shown that menstrual cycle changes from the Covid-19 vaccine are temporary. Clancy believes that when providers share the full range of vaccine side effects, people can increase their trust in “the vaccine, the science.”
“There’s a lot of literature showing that medical mistrust is one of the most pressing forces for people to get vaccinated,” said Clancy, an associate professor of anthropology at the University of Illinois at Urbana-Champaign and the paper’s co-author. “It’s a lot of comfort knowing that people won’t be surprised or worried and know what to expect.”
The results should be reassuring, experts said.
“The long-term effects of vaccination, in terms of altering, limiting cycle lengths or cycle flow,” said Dr. Christine Mullin, OB-GYN and chief of the Northwell Health and Fertility Center in Manhasset, New York, in a press release today. “Vaccines can throw off our cycle a bit. But it’s usually short-lived and react like any other stressor.
The findings confirm that people who experienced menopause but were laid off.
“A lot of people have told us that they’ve had those experiences, and that they’ve been told by their doctor, their friend, their spouse, their partner and (them) that it can’t happen,” Lee said.
They experienced changes in their periods
Lee and Clancy examined survey results from 39,129 menstruating adults. They include women, transgender men, non-binary people, people on long-term birth control, people who are postmenopausal, and those with disorders that are often excluded from research, such as endometriosis. Among those with regular menstrual cycles, 42% reported heavy bleeding following vaccination.
“In terms of who was more likely to see this effect in our sample…people who were Hispanic were more likely to see heavy bleeding. Older people in the premenopausal group were more likely to see heavy bleeding,” Lee said.(People) … They are more likely to see serious bleeding, such as endometriosis or fibroids.”
Other affected people: Regardless of the result, this includes people who were pregnant and who experienced other vaccine side effects such as fever or fatigue.
“In general, if you have more reactions, we would expect to see an increase in (menstrual changes),” Lee said.
Those who experienced postmenstrual bleeding were younger. “Maybe it’s because there’s less time since they’ve had their periods,” Lee said.
Some trans people on hormones also experience bleeding.
“We have people who don’t menstruate normally – both on long-acting, reversible birth control and sex-affirming hormones like testosterone – and we also have people who are postmenopausal, all of whom can experience bleeding,” he said. .
What causes changes in menstruation?
Clancy said many of the uterus’ “core functions are closely tied to the immune system” because of the changes in periods after the Covid-19 vaccine.
“One of the things that the uterus is constantly doing … is building tissue. It’s separating tissue. It’s breaking down. Menstruation itself is a process of tissue repair and tissue healing, just like wound healing is seen anywhere in the whole body,” she explained.
When people receive the vaccine, it stimulates immunity in the body.
“If you’ve got a lot of immune activity that’s always asking for bleeding and a bleeding response in the body, then you think, wait, is there a bleeding part in the body? So you would think that blood flow to that part of the body would be affected,” Clancy said.
Mullin added that any type of stress can affect a person’s menstrual cycle, and for some, receiving the Covid-19 vaccine comes with stress. Starting a new medication can often lead to changes in menstruation.
“The COVID vaccine creates anxiety in people,” she said. “Typically, we tell our patients that when they start birth control, they may notice something unusual in their periods or what they call bleeding. Although it’s a concern, I don’t think it’s anything to worry about long-term.”
Lee and Clancy plan to continue researching vaccines and menstruation, including research with some of the original survey participants.
“One thing we’re curious about is boosters, and also… how long does it take after the vaccination before you start to get back to normal?” Clancy said. “It’s important to measure this change in the context of how it affects the person’s quality of life.”