After receiving a COVID-19 vaccine, some women are reporting heavier menstrual cycles and more cramping. To date, there are no published scientific studies about a possible link, but researchers are looking into it.
A colleague told me she has heard from others that their periods were heavy post-vax. I'm curious whether other menstruators have noticed changes too? 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.
— Dr. Kate Clancy 🏳️🌈 (@KateClancy) February 24, 2021
Katharine Lee, a postdoctoral researcher in the Division of Public Health Sciences at Washington University’s School of Medicine, is part of that effort. On Friday’s St. Louis on the Air, she noted that menstrual cycles are incredibly variable — a strong illness or changes in eating or exercise can alter one’s period. Plus, when the body experiences inflammation — as it does after a vaccine produces a strong immune response — the menstrual cycle is likely to change as well.
Normal, healthy immune response - changes in inflammation/platelets should be part of immune activation from vaccines. In some people who have regular bleeding events (like menstruators) one would actually expect a little variability there as a result. No long term effect.
— Dr. Kate Clancy 🏳️🌈 (@KateClancy) April 23, 2021
Lee herself had abnormal menstruation after receiving a COVID-19 vaccine in February. Along with researcher Kate Clancy of the University of Illinois at Urbana-Champaign, she created a survey to catalog people’s period experiences after receiving COVID-19 vaccines. Within hours of posting the survey on Twitter, they received hundreds of responses. Two weeks later, 31,000 people have completed it.
The study is ongoing, but responses so far show that abnormal periods post-vaccine are not uncommon. However, Lee was quick to stress that there’s no evidence to suggest that people should avoid getting vaccinated for this reason.
“Get vaccinated folks; it’s better than having COVID,” she said.
Lee added that post-vaccination effects on the menstrual cycle are likely short term. If irregularity continues for months, she suggested contacting a physician to rule out anything serious.
In addition to discussing what she and Clancy hope to learn from their research, Lee dispelled some false beliefs (such as COVID-19 vaccines impacting people by proximity) and offered up reasons why people should more readily talk about and study menstrual cycles.
“St. Louis on the Air” brings you the stories of St. Louis and the people who live, work and create in our region. The show is hosted by Sarah Fenske and produced by Alex Heuer, Emily Woodbury, Evie Hemphill and Lara Hamdan. The audio engineer is Aaron Doerr.
