What You Need to Know

Getting vaccinated is critical to stop the spread of COVID-19. Still, women should avoid scheduling both their vaccine and breast imaging exams around the same time.

Why? A small percentage of women who receive the COVID-19 vaccine develop swollen lymph nodes under their arm on the same side as their vaccine injection. (This is a normal immune reaction to a vaccine). Because these swollen lymph nodes can appear on a mammogram or screening breast ultrasound, they can affect your results. These swollen lymph nodes usually return to normal on their own in a few days or weeks (1).

What happens if there are swollen lymph nodes on my breast imaging exam?

Depending on your medical history and when you received your vaccine, the breast radiologist may recommend that you return for an ultrasound of your underarm area and they also may recommend a follow up exam to show that the lymph nodes have returned to normal size.

When should I schedule my screening mammogram or screening breast ultrasound?

Try to schedule your screening before your first COVID-19 vaccine dose or at least 4-6 weeks after your second vaccine dose. This reduces the chance that swollen lymph nodes from the vaccine will appear on your mammogram or screening breast ultrasound.

What if my breast imaging exam is already scheduled?

Keep your vaccination appointment. Getting vaccinated is critical to stop the spread of COVID-19. Consider rescheduling your screening exam if possible before your vaccine. However, if you are already overdue for your screening exam or cannot reschedule within the next few months, keep your screening mammogram or screening breast ultrasound appointment and keep your COVID-19 vaccination appointment. Regular screenings ensure that breast cancer can be detected as early as possible. Both are very important to ensure that you stay healthy. It’s especially important to keep your breast imaging appointment if you are significantly overdue for screening. Remember: annual screening saves the most lives.

What should I tell the technologist on the day of my screening?

Notify your technologist if you have received a COVID-19 vaccine. Tell her when you received the vaccine, and which arm the vaccine was given in. State whether it’s your first or second dose. This information will help the breast radiologist interpreting your screening mammogram or screening breast ultrasound.

What if I have other breast problems?

If you have any changes in your breast or underarm, such as pain or a lump, contact your medical provider. The guidelines above are only for women with no breast symptoms who are scheduled for a COVID-19 vaccine.

(1) SBI Screening Mammography Recommendations for Women Receiving the COVID-19 Vaccine, Society of Breast Imaging, 2021