Swollen lymph nodes caused by vaccination are temporary, harmless and a sign that the vaccine is working, US doctors explain.

So you don't have to panic. But to avoid unnecessary anxiety and uncertainty, women planning to get a mammogram should know that swollen lymph nodes right after a vaccine dose might show up on a mammogram, the US Food and Drug Administration's top vaccine official said this week, CNN reports.

If you are a woman, and you're going to get a mammogram, and you get your booster shot, call and tell them you're getting it (or) you've gotten it," Dr. Peter Marks, head of the FDA's Center for Biologics Evaluation and Research, said at a town hall hosted by the Covid-19 Vaccine Education and Equity Project.