The CDC is advising people who are due for a mammogram to speak with their medical provider on how long they should wait until after they receive their vaccine to get their mammogram. The vaccine can cause lymph nodes under the arms to swell, which can cause a false reading on a mammogram. According to the CDC, some experts recommend getting a mammogram first before receiving the vaccine or waiting four to six weeks after being vaccinated to get a mammogram. For more details on this and how the vaccine affects other medical procedures visit https://www.cdc.gov/coronavirus/2019-ncov/vaccines/expect/other-procedures.html#