This case report details the unusual experience of a 19-year-old Canadian woman who experienced significant breast enlargement following her Covid-19 vaccination. Within six months of receiving the two-dose Pfizer vaccine, her breast size increased dramatically, from a B cup to a triple G cup. The growth began after the first dose, accompanied by a tingling sensation, and continued rapidly after the second dose. This unexpected and rapid change prompted her to seek medical attention, but her concerns, according to researchers, were not adequately addressed initially, leading to a sense of mistrust in the healthcare system.
Medical professionals eventually diagnosed the woman with pseudoangiomatous stromal hyperplasia (PASH), a rare condition characterized by abnormal cell growth and benign lumps in the breast tissue. Extensive testing ruled out other potential causes of such rapid breast growth, including hormonal imbalances, pregnancy, or medication. This diagnosis represents the first reported association between PASH and a vaccine, although fewer than 200 cases of PASH have been documented globally. While the exact causal relationship remains unclear, researchers speculate that the vaccine might induce temporary swelling in the lymph nodes, potentially leading to the appearance of enlarged breasts.
This phenomenon of increased breast size or altered breast shape post-vaccination was observed in some individuals during the initial vaccine rollout. At the time, it was attributed to axillary adenopathy, commonly known as swollen lymph nodes. Swollen lymph nodes, often located in the armpits, neck, and groin, typically indicate the body’s immune response to infection. Vaccines, designed to stimulate an immune response similar to a natural infection, can sometimes cause this temporary swelling. While acknowledged as a rare side effect, health authorities maintain that the benefits of vaccination far outweigh the potential risks.
In this specific case, the young woman had no prior health conditions. Examinations revealed swollen lymph nodes and dense blood vessels around her armpits, consistent with the enlarged breast tissue. While her breasts were swollen and saggy, no masses were detected. PASH, a benign condition first identified in 1986, results in non-cancerous lumps composed of specific cells within the breast tissue. This case raises the question of a potential link between Covid-19 vaccines and excessive breast growth, although further research is necessary to establish a definitive connection.
Eleven months after her vaccination, the woman underwent breast reduction surgery, removing a significant amount of tissue and reducing her breast size to a double D cup. Although no further growth has occurred, the surgery resulted in asymmetrical breasts, prompting her to consider further procedures to restore them to their pre-vaccination size and shape. This case underscores the importance of ongoing monitoring and research into the potential long-term effects of Covid-19 vaccines, even those considered rare.
This case coincides with a broader report from the Medicines and Healthcare products Regulatory Agency (MHRA) in the UK detailing a range of unusual side effects reported after Covid-19 vaccination. These reports include increased libido, decreased sex drive, eating disorders, paranoia, and even a case of a person developing a preference for cross-dressing after receiving the Pfizer vaccine. Other reported side effects include excessive flatulence after the AstraZeneca jab, fatigue, nausea, skin rashes, and increased gambling. The MHRA emphasizes that a reported reaction doesn’t necessarily imply a causal link with the vaccine but represents a suspected association that warrants further investigation. This reporting system serves as an early warning system to identify potential side effects and inform further research and safety monitoring.
