Women Experience Stronger Side Effects to COVID Vaccine

Many women have been reporting severe side effects after being vaccinated for COVID-19. Two frontline workers, Shelly and Scott Blomgren, were one of the first to receive the vaccine back in January. While they both received their shots at the same time, their reactions were night and day. Scott reported feeling fine, while Shelly struggled with “the worst body aches I’ve ever had in my life,” for two days, this came alongside many flu-like symptoms like chills, fever, and exhaustion.

A few days later at work, Shelly asked her colleagues about their vaccination experiences: of seven women, six of them experienced the same side effects she had and the last woman instead suffered a night of vomiting. Meanwhile, the men all complained only of a sore arm and some mild body or headaches, if they had any symptoms at all.

Experts say that this type of reaction to vaccines is normal among women. A study done in 2013 found that four times as many women reported allergic reactions to the flu vaccine than did men. Another one showed that women comprised 80% of anaphylactic reaction to vaccines. In the first month of vaccinations, over 79% of vaccine side effects were reported by women even though they received only 61.2% of the doses. This number can also be affected by the fact that it is likely that women are more likely to report side effects due to masculinity stereotypes.

Researchers say that the reason that women experience so many more side effects is because estrogen levels elicit a stronger immune response; so, while the side effects may be more intense, women and those with high estrogen levels are actually being poised to have a stronger and quicker immune response to viral threats. This is also seen with women who are premenopausal due to the higher levels of estrogen they experience.

The genetic differences seen between sexes may be influenced by immune related genes, which are mainly found on the X chromosome and women have two; recent research has shown that some 15% of genes on the second chromosome can be more highly expressed in women. Studies on intersex people have not yet been done to see how their genes and the expression of them can affect their reactions to vaccines.

On the flipside, testosterone has been linked to a weaker immune response in several studies and a study in March 2021 showed that giving hospitalized males with COVID-19 the female hormone progesterone actually improved their clinical outcomes.

Of course, experts say that regardless of the intensity of side effects, this should not deter anyone from receiving their vaccine; temporary symptoms are better than catching COVID and potentially becoming hospitalized. The presence of these side effects show that the vaccine is doing its job, instead, they can try to help minimize their side effects by talking to their doctor about what over-the-counter medications they can take and approved remedies to lessen the side effects.