Mammograms and the COVID-19 Vaccine: What Women Need to Know

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Yearly mammograms save lives by detecting cancer at earlier, more treatable stages. And the COVID-19 vaccine, of course, will save lives by preventing many people from getting and spreading the virus. But there’s a surprising side effect from the COVID vaccine that you will want to know about—especially if you have a mammogram scheduled soon.

During a mammogram, technicians image not only the breast but also the area near the underarm. Right now, some women who have had the covid vaccine are having an unexpected reaction

“Not everyone, but some patients we will see enlarged or swollen lymph nodes on the mammograms,” shared Holly Marshall, MD, division chief of breast imaging at University Hospital Cleveland Medical Center.

The U.S. Centers for Disease Control is reporting that 11% of COVID-19 vaccine recipients have swollen lymph nodes after the first dose. 16% have swelling after the second. The swelling starts about two to three days after the vaccine. That’s why doctors say it’s important for women to tell their providers if they have recently had a vaccine, which arm it was in, and if it was the first or second dose.

“This gives us information to help us read the mammogram. Other things such as cancer can cause swollen lymph nodes. So, that’s why we want to know the vaccine history,” explained Dr. Marshall.

Doctors say the swelling should go away in four to six weeks and is the body’s normal response to the vaccine.

“If the lymph nodes have not decreased in size in about two months, then it would be time to get it checked out, to come and have an ultrasound and make sure that there is nothing else going on,” shared Dr. Marshall.

The CDC reports cases of swollen lymph nodes in patients who have had the Pfizer vaccine and the Moderna vaccine. Doctors say sometimes the patients have felt the swelling under their arm and in other cases, they swollen lymph nodes are detected on the mammogram, but are not felt by the patient.

Contributors to this news report include: Cyndy McGrath, Executive & Field Producer;  Roque Correa, Editor.

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