To Protect Your Health and Peace of Mind, Schedule Your Mammogram Before COVID-19 Vaccination or Four Weeks After

Most of us know about the possible side effects of the COVID-19 vaccine, including mild pain, swelling, and feeling tired, achy or feverish. But there’s another side effect to be aware of, especially for women who need a mammogram. The vaccine can cause swelling of the axillary lymph nodes under the arm.

After vaccination, swollen lymph nodes can be a good thing. It’s a sign that the body is building the immunity it needs to fight the virus. But usually, when I see swollen lymph nodes on a mammogram, it’s an indication of something much worse, like metastatic breast cancer, lymphoma, or leukemia. The only way to tell if it’s a reaction to the vaccine or something more serious is by doing additional testing.

The last thing I want to do is call a woman back in for more tests if it’s not necessary. It’s frightening for her and makes the process more costly and time consuming. And during the pandemic, we want to limit unnecessary interactions between patients and caregivers to stop the spread of COVID-19. 

When to schedule your mammogram

We advise women to schedule their routine screening mammogram any time before their first dose of the vaccine, or to wait until four weeks after their final dose. If you have a choice between the vaccine and a mammogram, get the vaccine! We have a fire raging with this virus and we need to put that out as soon as possible, especially with the rise of new variants. 


Here are a few different scenarios and how to handle them:

  • You feel a lump under your arm 
    • If the lump arises within a few days of vaccination, wait four weeks to have a mammogram; if the lump goes away, just return to your normal annual screening schedule. 
    • If you haven’t been recently vaccinated (meaning you are four weeks out from your second dose), you may proceed with your annual mammogram. 
  • You feel a lump in your breast or have other symptoms like bloody discharge from a nipple or scaling around the nipple. Don’t wait; schedule a mammogram right away. 
  • You need a six-month follow-up mammogram after lumpectomy for breast cancer. Wait four weeks before returning for your exam.
  • You are scheduled for a different imaging test, like an MRI or CT scan. Often these tests are done in urgent medical situations and should not be postponed. In this case, let your physician know in advance that you’ve had the vaccine recently.

Delay, but don't forget about your exam

I want my patients to remember that we’re calling for a short delay of their mammogram, not a cancellation; and this message is only for a small subsection of women who’ve had the vaccine within the previous four weeks. 

Breast cancer doesn’t stop because of the pandemic; it kills 40,000 to 50,000 American women each year. Postponing your mammogram by a month or two would not be that impactful, but postponing it by a year could be. 

Who should get a mammogram?

  • Women who are at average risk for breast cancer should begin annual screening mammography at the age of 40.
  • Women who are high-risk (mother or sister with a history of breast cancer) should talk to their doctor about the right time to start.

Watch Dr. Brett Parkinson discuss mammograms and COVID-19 vaccination