The Truth About The COVID Vaccine Changing Your Boob Size

Misinformation and medical myths have plagued the COVID-19 vaccine rollout since it began. Unfounded claims that the jabs contain toxic chemicals, can 'shed' to others through inhalation or skin contact and are part of a plan to sterilise and depopulate the world have spread globally.

A patchwork of rumours specifically target women’s health, from menstruation to fertility, exploiting gaps in healthcare and available data. Now, despite there being no evidence, new misinformation is swarming on- and offline about COVID-19 vaccines, boobs, breast cancer and boob size.

The first baseless rumour is that the vaccines are somehow causing breast cancer, with people suggesting the jab has caused symptoms or led to a diagnosis. A number of women have reported irregular lumps near their breasts since receiving COVID-19 vaccines but experts on breast health say this is not breast cancer but part of the body’s intended immune response to the vaccine.

"One of the more uncommon side effects of the COVID-19 vaccine is enlarged lymph nodes, including in the armpit," explains Jane Murphy, a senior clinical nurse specialist at UK charity Breast Cancer Now. Lymph nodes – bean-shaped pockets of cells located around the body – can swell in reaction to any vaccine or illness as the immune system fights infection, she says. "It’s usually a temporary reaction and goes down after a few weeks, but for some people it may be slightly longer." According to Public Health England (PHE), there is a less than 1% chance of enlarged lymph nodes after vaccination.

"There’s absolutely no link between the vaccine and breast swelling or cancer," says Dr Sarah Vinnicombe, chair of the British Society of Breast Radiology (BSBR). 

Breast Cancer Now has noticed a number of calls to its helpline from recent vaccine recipients. "We’ve heard from some women with concerns about the side effects of the COVID-19 vaccine, including experiencing enlarged lymph nodes," said a spokesperson for the charity. 

Public Health England has advised that routine breast screenings continue to be offered to women aged 50 to 70 every three years. Dr Vinnicombe says that pausing them in 2020 due to the pandemic has caused ongoing delays. "We’re trying to make sure people don’t miss appointments so it’s been a massive undertaking for the breast imaging community to play catch-up."

Murphy says that women may want to wait a few weeks after being vaccinated to attend a breast screening appointment or note a recent vaccine to the practitioner. "This is because of the potential for the swelling of lymph nodes in one armpit (the side of the injection) following vaccination, which could be detected during routine screening and cause unnecessary concern." Murphy advises those concerned to speak to their doctor or call Breast Cancer Now’s helpline.

Despite the uncommon and fleeting nature of the side effect, false rumours that the vaccine causes cancer can damage people’s trust in vaccinations and increase hesitancy. While vaccine scepticism is generally falling across the UK according to the Office for National Statistics, authorities are still having trouble convincing some under-30s, whose uptake is lower than the average for older age groups. By 19th August, just over six million 18 to 29-year-olds in England had been vaccinated – around 71%, according to the latest available population estimates. 

The swelling of lymph nodes post-vaccine has also helped spawn another baseless rumour – that Pfizer’s COVID-19 vaccine increases breast size. Streams of women have claimed their boobs grew after vaccination in what’s become known as the 'Pfizer boob job'. One of the first to make the claim online was a young TikTok user who excitedly alleged that her boobs had grown two cup sizes since the vaccine. The video has been viewed more than 76,900 times, with scores of commenters expressing hope for the rumour to be true and posting fingers-crossed emoji.

Some women may have genuinely felt an increase in breast size since being vaccinated but it’s likely due to enlarged lymph nodes, which is temporary, says Murphy. "It’s not likely to be breast tissue."

The rumour may appear relatively harmless but for some people it’s cast doubt on the COVID-19 vaccines. In response to the viral video, dozens of users wrote that they were scared to get the vaccine, with one writing she would "become an anti vaxxer" if her boobs grew afterwards. A Portuguese news article, shared more than 4,000 times on Facebook, also picked up on women reporting bigger boobs post-vaccine but failed to provide any context or an explanation of lymph node swelling. Others falsely claimed that the perceived phenomenon must be a sign of vaccine safety issues. The Medicines and Healthcare products Regulatory Agency (MHRA) has determined that the COVID-19 vaccines in use in the UK are safe and effective.

For any young women still noticing breast changes a few weeks after vaccination, Breast Cancer Now recommends speaking to your GP and getting checked out. "A lump or swelling in the breast, upper chest or armpit can be a sign of breast cancer and it’s vital that during the COVID-19 pandemic women still get in touch with their GP if they find any new or unusual breast changes," a spokesperson for the charity said.

Even when rumours about COVID-19 vaccines and women’s health are shared unintentionally and don’t appear overtly harmful, they can contribute to our disordered information ecosystem and confuse or concern people. Swollen glands alone may not be serious or long-lasting but the side effect may prove to be a timely reminder about breast checking. With regular self-examinations, women will be better equipped to spot a real change that needs to be checked out.

For support services, contact Breast Cancer Now’s helpline on 0808 800 6000. Check signs and symptoms of breast cancer on the charity’s website.