Fact Check Friday: Can the Pfizer and Moderna mRNA vaccines cause infertility?

Posted at 7:54 AM, Feb 26, 2021
and last updated 2021-02-26 08:59:52-05

As a third coronavirus vaccine may get FDA emergency approval today, scientists and doctors are still pushing back against rumors that the Pfizer and Moderna mRNA vaccines cause infertility.

The World Health Organization said it’s simply not true.

“The vaccines we give cannot cause infertility, this is a rumor that has gone around about many different vaccines and there’s no truth to the rumor,” said Dr. Katherine O'Brien, director of the Department of Immunization, Vaccines and Biologicals at the WHO. “There’s no vaccine that causes infertility.”

According to the American Society for Reproductive Medicine (ASRM), the latest rumor started in January by two European doctors who claimed the vaccine “contains a spike protein called Syncytin-1, vital for the formation of human placenta in women.”

Dr. Emily Defranco, director of maternal-fetal medicine at the University of Cincinnati, said scientists found the proteins are not biologically similar.

“And so developing an antibody against the COVID virus, wouldn't even theoretically develop an antibody that might be harmful to this placenta protein,” Defranco said.

ASRM in its January editorial said that since our bodies naturally create the antibodies, they would have expected to see an increased risk of miscarriages in pregnant women who had the coronavirus, and that’s not played out by the data.

For Defranco, the message is simple.

“Try to debunk any of these myths regarding danger related to vaccines. So that, you know, we don't continue to drive vaccine hesitancy,” Defranco said.

Defranco said those considering starting or expanding your family should talk to a healthcare provider to make an informed decision. Don’t base it on what you read on social media.

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