Female breast oncologist reviews the scans from a mammogram.

Does the COVID-19 Vaccine Have an Effect On Mammogram Screenings?

We know about the common COVID-19 vaccine symptoms like site injection soreness, fever, and cough. However, we haven’t heard much about a side effect that can cause misreadings in mammogram screening: enlarged lymph nodes. Some women who receive the COVID-19 vaccine develop swollen lymph nodes under their arm on the same side as their injection. This is a normal immune response to receiving a vaccine, but, if unaware, may cause some alarm on a routine mammogram screening.

What do swollen lymph nodes on a mammogram mean?

When you go in for an annual mammogram screening, radiologists are looking for anything unusual in the breasts and armpits. Swollen lymph nodes can be a rare sign of cancer. Depending on your medical history and when you received your COVID-19 vaccine, the breast radiologist may recommend follow-up exams to see if the lymph nodes have returned to normal size. 

If I just got my COVID-19 vaccine, when should I schedule my mammogram?

There is a difference between screening mammograms and diagnostic mammograms. Screening mammography is performed on people with no symptoms. If you recently received your COVID-19 vaccine and need to schedule a screening mammogram, the Society of Breast Imaging recommends waiting six weeks to ensure lymph nodes have returned to normal size. However, diagnostic mammography should not be delayed. If you are experiencing common signs of breast cancer, like a lump or abnormal discharge of the nipple, do not hesitate to notify your healthcare provider to then schedule a diagnostic mammogram. 

What if I have other breast problems after receiving my COVID-19 vaccine?

If you have any changes in your breast or underarm — like a lump, discoloration, nipple discharge, or pain — do not hesitate to reach out to your medical provider. The guidelines from the Society of Breast Imaging to wait six weeks for screening are only for women with no breast symptoms who are scheduled for a COVID-19 vaccine. 

Do you need to schedule your annual mammogram screening? After waiting six weeks from getting your COVID-19 vaccine, schedule your mammogram with St. Joseph Health

CDC | COVID-19 vaccination and other medical procedures
SBI | Mammogram Screening Recommendation
Healthline | COVID-19 Vaccine Can Cause 'False Positives' On Breast Cancer Mammograms

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