Women across the country are turning out more than men to get their COVID-19 vaccine, suggesting women are overcoming any potential hesitancy surrounding immunization in greater numbers than men.
Data from the Centers for Disease Control and Prevention (CDC) shows that more than 65 million American women, or 54.3 percent, have gotten at least one COVID-19 vaccine dose. Women make up 50.8 percent of the U.S. population.
In the meantime, almost 55 million men, or 45.7 percent, have received at least one dose.
The trend is relatively consistent across states, as last week, Kaiser Health News reported that the 38 states, and Washington, D.C., that break down vaccinations by gender all showed that more women received the shot than men.
The data implies that women are surmounting any concerns about receiving the COVID-19 vaccine, even as women are more likely to report minor side effects as well as the incredibly rare major side effects, such as the cases of blood clots that halted the Johnson & Johnson vaccinations.
Side effects that are considered minor but may cause concern to individuals include fatigue, sore arm, low-grade fever, as well as additionally reported rare lymph node swelling, which in some cases has caused “false positives” in breast cancer mammograms.
"[V]axes have side effects and it's ok. Let's remember transparency in medicine is better than gaslighting if the goal is reducing vax hesitancy," Kathryn Clancy, an associate professor of anthropology at the University of Illinois, wrote on Twitter this week after launching a survey of women's possible responses to the vaccine.
Women’s higher turnout for vaccinations could be attributed to several different factors, according to experts, including their traditional role as a caretaker leading many to be on top of vaccination appointments in order to make them for family members.
Earlier in the vaccination process, experts said that women were getting vaccinated at higher rates because they made up more of the prioritized groups, including health care workers and essential workers as well as older Americans, since women typically live longer than men.
But the gap has persisted since the vaccine has become available to more people and now, as of Monday, to all adults nationwide.
Rosemary Morgan, a research scientist at the Johns Hopkins Bloomberg School of Public Health, pointed to studies that determined that women are more likely to be worried about COVID-19 and more likely to follow health precautions.
“Because of this, does that lead into their desire to get the COVID vaccine?” Morgan said. “Whereas if men are not as worried about the pandemic, so they're not taking many precautions, does that affect their desire to get a COVID-19 vaccine?”
Other research has shown that women were “more adversely impacted” by the pandemic, with additional child care responsibilities and lost jobs, indicating they may be more ready to move on and see the vaccine as “the way out of this,” said Rebecca Wurtz, an associate professor of health policy and management at the University of Minnesota.
“A combination of wanting to get back to normal and being willing to endure trivial side effects from the vaccine are the main reasons why women” are getting the vaccine at higher rates, she said.
But vaccination data also demonstrates that women are more likely to report both minor and major side effects after their immunizations.
Experts cited women’s more robust immune systems as possible reasoning for minor and major side effects to the vaccine. Morgan, from Johns Hopkins, said the stronger immune response may indicate women might not need as much dosage as men. Others said women may just be reporting side effects at a higher rate than men, possibly due to men being more likely to delay health care treatment.
Still, experts agreed such reactions signal the vaccine is working, and the immune system is responding to the vaccine.
“So if anything, it's a positive thing,” Wurtz said.
She added it’s “likely” the prevalence of estrogen in women combined with their strong immune system “are working together to cause” the uncommon blood clot cases among Johson & Johnson and AstraZeneca recipients.
Federal authorities called for a pause in administering the Johnson & Johnson vaccine last week after six women experienced an usual blood clotting syndrome called cerebral venous sinus thrombosis. These six cases, among women aged 18 to 48, occurred out of the more than 6.8 million Johnson & Johnson doses given across the country.
Two other cases of general blood clotting were added to the list later in the week, including one involving a man who received the vaccine during a clinical trial.
The independent advisory panel for the CDC ultimately decided to continue the temporary halt, until at least Friday, allowing the group to gather more data on the rare blood clot cases.
David Wohl, a professor of medicine in the division of infectious diseases at the University of North Carolina at Chapel Hill, highlighted that uncommon side effects to vaccines is not “a new phenomenon” and that COVID-19 is more likely to cause blood clots.
“So if you want to avoid clots, COVID-19 causes many more clots than any vaccine ever will and kills – you can't even compare the mortality from COVID-19,” he said.
The age group of the women affected in the Johnson & Johnson cases prompted some to speculate hormonal birth control played a role in the cases. But experts say it's unlikely there's additional risk involved to women taking such birth control.
Last week, Peter Marks, the director of the Center for Biologics Evaluation and Research at the Food and Drug Administration, responded by saying “it’s not clear that there’s any association” between the cases and birth control.
Women’s health expert Jennifer Wider noted that years of studying birth control has led scientists to identify risk factors for blood clots among those who smoke, who are obese and who live a “sedentary lifestyle."
“When it comes to the Johnson & Johnson vaccine, these are not known risk factors at all,” she said. “I’m not saying that they won't be down the road, but my guess is not, because you have 6.8 million people, and many of which are probably obese in this country because we have an epidemic.”
Some women also accused health officials of taking the risk of blood clotting more seriously in the vaccine than with birth control.
Critics of the ongoing Johnson & Johnson pause have pointed to the rarity of the cases compared to the chances to get blood clots while taking oral birth control, which is widely considered safe. Up to 9 in 10,000 women report blood clots from that type of birth control, which is more than the 1 in 1.1 million with the Johnson & Johnson blood clots.
Experts say comparing the two types of low blood clot risks is like comparing apples and oranges, as the most common blood clot due to birth control starts in the leg and could travel to the lungs, requiring different treatment than the blood clots occurring after vaccination.
Concerns about vaccinations possibly causing rare blood clots first surfaced as the AstraZeneca vaccine was administered in Europe, with most patients being under 55 and women. The link is not clear because women were getting the shot at higher rates in some countries. Since then, most European countries have resumed AstraZeneca vaccinations, restricting access to only older individuals.
Women have also reported other side effects to the vaccine, with radiologists saying they have noticed swelling in lymph nodes under the armpit during mammograms. Such cases involving men are also being reported but less so as men usually don’t get mammograms to check for breast cancer.
As a result, the Society of Breast Imaging recommends scheduling a regular mammogram before getting the vaccine or at least one month after the second dose.
The American Society for Reproductive Medicine also advises women scheduled for fertility surgeries, such as egg retrieval, embryo transfer and intrauterine insemination to not get the vaccine three days before and three days after the procedure to help professionals distinguish between the effects of the shot and the surgery.
The New York Times in a lengthy piece about experiences women have had with COVID-19 vaccines also reported that some women have observed changes in their periods after taking the vaccine. It noted such evidence is anecdotal and quoted a reproductive health expert saying it was unlikely the COVID-19 vaccines would affect menstrual cycles.
Regardless of publicity around possible side effects, women were more likely than men to say they would take "any" vaccine, regardless of manufacturer, at 60 percent in an Economist-YouGov poll released this week.
CORRECTION: An earlier version of this story incorrectly described a study from Tongji Hospital in China. That study said some women may experience changes in their menstrual cycle following a COVID-19 infection.