Sen. Ron Johnson, R-Wis., told a Fox News Digital interviewer on August 10 that there was "an 82% miscarriage rate with women who got the (COVID-19 vaccine) injection in the first or second trimester". Sen. Rand Paul, R-Ky., helped push the framing across social media.
That number is not what the underlying research found. It has been circulating since 2021, when a New England Journal of Medicine safety report was reinterpreted by excluding most of the women it followed.
Public health experts warn the misinformation risks scaring pregnant patients away from a vaccine authorities still recommend.
What the actual studies found
PolitiFact walked through the arithmetic in a fact-check published August 12. The 2021 v-safe pregnancy registry tracked 3,958 vaccinated people. Among those with a completed pregnancy by the study cutoff, there were 104 miscarriages across 827 pregnancies, a rate of 12.6 percent.
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That figure sits inside the normal range for early pregnancy loss in the general population.
A follow-up NEJM analysis of 2,456 people vaccinated before 20 weeks of gestation landed at a cumulative miscarriage risk between 12.8 and 14.1 percent. A March 2026 study of 12,097 women reported a rate of 13.5 percent.
The largest systematic review to date, published in Human Reproduction in February 2023, pooled 21 studies covering 149,685 women. The authors found "no evidence that COVID-19 vaccines are associated with an increased risk of miscarriage."
The pooled miscarriage rate among vaccinated women was 9 percent, and the risk ratio compared to unvaccinated women was 1.07.
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Where the 82 percent figure came from
According to the PolitiFact fact-check, Johnson arrived at his number by removing 700 vaccinated women from the denominator, the ones who received their shots in the third trimester and could not, by definition, have had a first- or second-trimester miscarriage. That left 127 women, and the math was rebuilt on that much smaller pool.
The original researchers never reported an 82 percent figure. Independent fact-checkers have flagged the same recalculation each time it has resurfaced since 2021.
What Fauci actually wrote
The current wave of coverage started with text messages pulled from Anthony Fauci's government cellphone. Republican Sens. Johnson and Paul released them on August 10, 2026, after the Department of Health and Human Services turned over the device.
In a January 25, 2021 exchange with then-CDC Director Rochelle Walensky and Vivek Murthy, Fauci wrote that fever from a second mRNA vaccine dose "theoretically could be associated with miscarriage in the 1st trimester". Walensky called it a good point, especially after dose two. Murthy agreed.
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Days later, on February 3, 2021, Fauci said publicly that the FDA had found "no red flags about that, about pregnant women" among the roughly 10,000 vaccinated women tracked at that stage.
The private text reflected pre-data speculation, not a finding. By the time Fauci spoke publicly, the earliest safety monitoring data was coming in and it did not show a signal.
What health authorities say now
Krutika Kuppalli, an infectious disease doctor and professor at the University of Texas Southwestern Medical Center, told PolitiFact that "studies involving more than 1 million pregnancies worldwide have likewise found no increased risk of miscarriage, stillbirth, preterm delivery, or birth defects".
The American College of Obstetricians and Gynecologists continues to recommend COVID-19 vaccination for pregnant patients. That guidance appeared in ACOG's first independent immunization schedule, released after the CDC dropped its blanket pregnancy recommendation in May 2025. "We are all about the science," said Laura Riley, MD, chair of ACOG's Immunization, Infectious Disease, and Public Health Preparedness Expert Work Group.
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Pregnant patients weighing what to do this fall should raise the question with their obstetrician or primary care doctor.
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This article is made and published by Jesper Bengtson, who may have used AI in the preparation.