And even if you do feel something, you don’t have to put off your annual screening-especially if it would be hard to reschedule. If you have a mammogram scheduled and were recently vaccinated but don’t feel any kind of a lump or bump, do not reschedule your mammogram. “Worst case, if they weren’t sure on that mammogram, they would either bring you back for a repeat mammogram in a couple of months or they would do an ultrasound of the area.” “Even if you feel a lump or a bump there in your armpit, it is unlikely that that’s going to be mistaken for a breast lump or a breast nodule that would then lead to biopsy or further imaging,” Dr. Some women are wondering what to do about mammograms: Will an armpit lump from the vaccine complicate the results? “If it seems like it’s going down and going away over the course of the week, which it almost always does, then I don’t think any further kind of follow-up or concern is needed-particularly if it’s in the armpit rather than in the main part of the breast.” Should you delay your mammogram? “If it doesn’t seem like it’s getting any smaller over the course of about a week, then I think that is definitely time to come in and get it checked out in the office,” Dr. (And know that conditions other than cancer can cause a persistent swollen lymph node, but you’ll want to see a doctor to know for sure.) Ruff and Brimmage say that if you feel swelling in your lymph nodes and recently had a COVID-19 vaccine, wait a week to 10 days to see if the swelling decreases. That’s because when breast cancer spreads outside of the breasts, it often goes to the lymph nodes under the arms.īoth Drs. How do you know if a swollen lymph node might be cancerous?īreast cancer also can cause a swollen lymph node in the armpit. “The reason that you are getting swelling in your armpit after the COVID vaccine is because your body is working really hard to mount an immune response so that it can protect you against COVID,” says UNC Health family medicine physician Sarah Ruff, MD. The vaccine is still working in your body.) (That said, if you don’t notice side effects, don’t worry. Experiencing mild side effects after a vaccination, such as a slight fever, body aches and swollen lymph nodes, is your immune system telling you that it’s doing exactly what you want it to do-respond to the vaccine and produce antibodies.

Then, if you’re exposed to COVID-19, those antibodies are ready to recognize the virus, resulting in either no infection or a less serious infection. It is training your body to make antibodies to fight the virus. Here’s why: The aim of the COVID-19 vaccine is to get your immune system to launch a response to what it thinks is the COVID-19 virus. Why would the vaccines cause swollen lymph nodes?īecause the COVID-19 vaccines are given in your arm, they can activate the lymph nodes in your armpit and cause swelling there. Some people with breast cancer experience swollen lymph nodes in the armpit, which might cause anxiety after vaccination for women who don’t know to expect it. If you get a sexually transmitted disease or vaginal infection, the lymph nodes in your groin might swell. For example, if you have strep throat, the lymph nodes in your neck become swollen. The lymph nodes closest to the affected body part are usually the ones that swell.

They are activated-and thus become swollen-when they detect a harmful substance and try to remove it from your body. They are located throughout your body, including in the neck, armpits and groin. Lymph nodes filter out harmful substances in your body, such as bacteria and viruses. “It’s normal after either a vaccination, an illness or infection for the lymph nodes to be enlarged because that’s where the big immune reaction is happening.”

They recognize an illness and then activate the immune system,” says Brian Brimmage, MD, an obstetrician who delivers babies at UNC REX Healthcare. “Lymph nodes are primarily where your immune cells reside. This is your immune system at work, building up its defenses to COVID-19. As more people are getting the coronavirus disease 2019 (COVID-19) vaccines, doctors are noticing an interesting-but not unusual-side effect: swollen lymph nodes, especially under the armpits.

Shotty lymph nodes after infection