Open Accessibility Menu
Hide

Can the COVID Vaccine Affect My Period?

Can the COVID Vaccine Affect My Period?

You’ve seen the vaccine selfies and heard about the side effects after the second dose, but now that more than half of all adults in the U.S. have been vaccinated against COVID, some women are also reporting changes in their period following the vaccine. While the menstrual changes are all anecdotal at this point, it wouldn’t be surprising for research to validate the claims. A person’s hormones are tightly connected to their immune response. Some researchers have even theorized that sex hormones like estrogen and progesterone are the reason women are less likely to experience severe cases of COVID.

Some women have reported late periods and heavier flows after their vaccines. These changes appear to be temporary, with cycles returning back to normal in a couple of months. That’s good news, and researchers are still working to understand more about why some women are experiencing these changes.

In general, women’s menstrual cycles are affected by a host of different factors, from changes in diet and exercise, to stress, to lack of sleep and some medications. Women typically mount greater immune response to vaccines than men, which means they may feel worse after any vaccination. That stress on the immune system could theoretically impact your period. Hormones act as signals to your brain during the menstrual cycle, and those signals can be disrupted when the body is affected by an infection or even a vaccine.

With COVID-19, there have been some small studies showing that the virus creates stress on the body, leading to irregular menstrual cycles for some. But the bottom line is that there just isn’t enough data to show that the vaccine itself could impact your period.

If the change in your cycle continues after a couple of months or if your period starts to be heavy enough to soak a pad or a tampon each hour, call your doctor’s office. There may be something else at play.