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There’s Unclear Link Between Blood Clots, the J&J Covid-19 Vaccine and Women


Photo by Reproductive Health Supplies Coalition on Unsplash

Six women who developed an extremely rare blood clotting condition weeks after receiving the Johnson & Johnson Covid-19 vaccine have prompted an urgent discussion about the risks for women.


While only six people out of 7 million who received the vaccine experienced the bizarre side effect, the fact that all six were women between the ages of 18 and 48 led many to assume birth control, which comes with its own blood clotting risks, might have had something to do with it. Others have simply pointed out that the risk of the rare blood clotting disorder, called cerebral venous sinus thrombosis, is equal to about 1 per 1.1 million administered vaccines––a rate that’s lower than the risk of blood clots from birth control medications.


In a rare move, the Federal Drug Administration recommended a pause of the J&J vaccine until the link to blood clotting can be fully investigated. The pause affects federal vaccination sites, though states were free to make their own decisions about continuing administration of the J&J vaccine.


However, it’s not clear yet what the risk is to women––and if birth control plays any role.


“It’s not clear that there’s any association with oral contraceptive pill birth control” Peter Marks, MD, PhD, of the FDA, said in a press briefing this month.


And many experts say comparing the risks of birth control and the Covid-19 vaccine is futile. For one, the blood clotting seen with the J&J vaccine is different than with hormonal birth control.


“We’re talking about a vaccine during a pandemic that’s being administered to millions of people under an emergency-use authorization, versus hormonal birth control, which has decades and decades and decades of science and safety data behind it, and very well-known risks associated with it that are known by all of the providers who would prescribe it,” Jen Villavicencio, MD, an OB/GYN based in Michigan family and planning fellow at the American College of Obstetricians and Gynecologists, told The Lilly.


Clotting concerns have also arisen around Europe’s AstraZeneca vaccine. And two more blood clotting incidences associated with the J&J vaccine are now being investigated.


According to FDA Commissioner Scott Gottlieb, “most consumers” shouldn’t be concerned.

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