Side effects from vaccine reported more by women
Reports of COVID-19 vaccine side effects support what many have anecdotally observed: women shoulder the bigger burden. Of nearly 7,000 reports processed through the Centers for Disease Control and Prevention’s Vaccine Adverse Event Reporting System from Dec. 14 to Jan. 13, more than 79% came from women. The most frequently reported side effects were headache, fatigue and dizziness.
Women also are more likely than men to experience some of the vaccine’s more unusual side effects, such as an itchy red rash that appears at the injection site commonly known as COVID arm or Moderna arm, as about 95% of the reactions occur with the Moderna vaccine. Overall, women account for 77% of the Moderna vaccine’s reported side effects.
These side effects – even if unusual – are a good sign the vaccine is working to arm the body’s immune system against the coronavirus. But why are women more likely to experience them than men? Health experts said it might be from biological differences, inconsistent reporting by men and gender bias in clinical trials.
Women exhibit a greater immune response to vaccines than men, experts said, which might partially explain why more of them have reported side effects to the COVID-19 vaccine. “From a biological perspective, women and girls produce sometimes twice as many infection fighting antibodies from vaccines,” said Rosemary Morgan, a researcher at Johns Hopkins Bloomberg School of Public Health.
Although there’s no data comparing men and women’s immune response to the COVID-19 vaccine, researchers from a 2019 study found women developed greater cytokine and antibody responses compared to men after getting the flu vaccine. Also, men might be reporting side effects less frequently, health experts said. “We don’t have more robust evidence that look at reporting side effects ... but what we do know is that it is possible that women may be reporting more side effects than men due to what we know about how men behave in relation to health care,” Morgan said.
Studies have showed women are more likely than men to use health care services, according to the World Health Organization.
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