Stay Curious. Stay Connected.
MailNewsletters♡Donate Now
Sign up
*Password must be at least 8 characters and contain one uppercase letter, one lowercase letter, one number and one symbol.
Already have an account?
By submitting, you consent that you are at least 18 years of age and to receive information about MPR's or APMG entities' programs and offerings. The personally identifying information you provide will not be sold, shared, or used for purposes other than to communicate with you about MPR, APMG entities, and its sponsors. You may opt-out at any time clicking the unsubscribe link at the bottom of any email communication. View our Privacy Policy.
Sign in to your profile
Forgot Password?
New to MPR News?
Welcome back
to news
for you
Reset Password

Enter the username on file and we'll send you a code to reset your password.

Still require assistance or not sure what your User Name is?
Welcome back
to news
for you
Email Verification

A verification code has been emailed to

Still awaiting the code?
COVID-19
The Associated Press

Can COVID-19 vaccines affect your period?

A close up of a vial and needle.
A nurse draws a dose of the COVID-19 vaccine in January at the Earle Brown Heritage Center in Brooklyn Center, Minn. It's not yet known if COVID-19 vaccines can affect your period, but researchers are starting to study the issue.
Christine T. Nguyen | MPR News file

Go Deeper.

Create an account or log in to save stories.

Log inCreate a free Account

Like this?

Thanks for liking this story! We have added it to a list of your favorite stories.

Show me!

Can COVID-19 vaccines affect your period?

It's not known, but researchers are starting to study the issue.

Vaccines are designed to activate your immune system, and some experts have wondered if that could temporarily disrupt menstrual cycles.

So far, reports of irregular bleeding have been anecdotal. And it's hard to draw any links to the vaccines since changes could be the result of other factors including stress, diet and exercise habits. There's also a lack of data tracking changes to menstrual cycles after vaccines in general.

If scientists do eventually find a link between the vaccine and short-term changes in bleeding, experts say that would be no reason to avoid getting vaccinated. "The benefits of taking the vaccine certainly way outweigh putting up with one heavy period, if indeed they're related," said Dr. Mary Jane Minkin, a gynecologist and a professor at the Yale University School of Medicine.

Researchers recently launched a survey to begin gathering data. The findings won't determine whether there's a relationship between COVID-19 vaccines and menstrual changes, but could help form the basis for further research, said Katharine Lee, one of the researchers, who is based at Washington University in St. Louis.

Dr. Jen Gunter, an obstetrician and gynecologist in the San Francisco Bay Area, said a link is possible, since the uterine lining, which is shed during menstruation, contains immune cells that help protect the uterus.

There's no evidence that any vaccines, including COVID-19 vaccines, affect fertility, according to the U.S. Centers for Disease Control and Prevention and the American College of Obstetricians and Gynecologists.