Women should allow six weeks between their COVID-19 vaccine and a screening mammogram because of the phenomenon of vaccine-induced lymphadenopathy, Australian radiologists advise.

Recent reports from the US indicate the immune response to the vaccine can manifest as unilateral axillary lymphadenopathy on the vaccination side, the Royal Australian and New Zealand College of Radiologists said in a statement.

This could present as a palpable lump and “inadvertently” show up on breast imaging, the college added.

“Women are therefore advised to have their screening mammograms before being vaccinated or six weeks after.”