Should I Wait to Get a Mammogram if I Just Got a COVID Vaccine?

The immune response created by vaccines sometimes causes mild swelling of lymph nodes in the underarm area. This type of reaction is uncommon with most vaccines, but is a more common side effect (10-15%) of the current COVID vaccines. This swelling is not harmful, but it can cause a false positive result on a mammogram, ultrasound, or breast MRI because the tests detect the swollen lymph nodes. If a mammogram detects swollen lymph nodes, you may need extra testing to ensure that you do not have breast cancer.

The Society of Breast Imaging is recommending that women consider scheduling a screening mammogram either:

  • Before the first dose of a COVID vaccine or 
  • 4-6 weeks after the second dose of a COVID vaccine.  

If you need a diagnostic mammogram, have breast cancer symptoms, a current breast problem, or a recent abnormal mammogram, it is not recommended that you wait.  It is better to catch breast cancer early if you have concerning symptoms.

Talk to your doctor and to let them know that you have just had a COVID vaccine to get personalized advice about scheduling your appointment. When speaking to your doctor, it is helpful to have the date of your vaccination and note the side on which you got your vaccine.

Last update: March 2, 2021, 15:00 EST

Science review: ERS, JAB