Text messages from January 2021 show America's top federal health officials privately debating whether a cytokine response (the immune reaction that produces fever and body aches after a vaccine dose) from the COVID mRNA shot could raise miscarriage risk in the first trimester. The messages, released Monday by Sens. Ron Johnson of Wisconsin and Rand Paul of Kentucky, captured a conversation between Dr. Anthony Fauci, then-CDC Director Dr. Rochelle Walensky, and Dr. Vivek Murthy, who later became President Biden's surgeon general.

What the texts actually say

Dr. Vivek Murthy opened the exchange by asking whether officials had seen adverse outcomes among pregnant women already vaccinated, and whether vaccination timing within pregnancy mattered. Fauci responded that there was "no data or theoretical reason" to prefer vaccination earlier or later in pregnancy. He also addressed a fear circulating publicly: that mRNA vaccines could alter human genes. That concern, he wrote, was a misconception.

Later that same evening, the conversation shifted. Because many vaccinated people develop significant cytokine-related symptoms and fever after a second dose, Fauci wrote, that reaction "theoretically could be associated with miscarriage in the 1st trimester." Walensky replied that it was "definitely a good point, esp after dose two." Murthy said he had been hearing concerns about mRNA causing mutations in a developing fetus and called Fauci's observation on the cytokine response "a really good point."

The WHO recommendation and the risk trade-off

The following day, Murthy flagged a World Health Organization recommendation advising against Moderna's vaccine in pregnant women, citing limited available data. Fauci's response framed the choice as a balance of risks. He wrote that more than 10,000 pregnant women had already been vaccinated with no issues reported. Animal toxicology studies had raised no red flags. Guidance from the Food and Drug Administration, the Advisory Committee on Immunization Practices, and the American College of Obstetricians and Gynecologists all permitted pregnant women to decide for themselves.

Murthy warned that a strong recommendation against vaccination, built on an absence of data rather than evidence of harm, could be "potentially quite damaging to public confidence among pregnant women." Walensky agreed and said she would raise the issue at an upcoming Advisory Committee on Immunization Practices meeting. The exchange appeared on page two of documents released by the Senate committee Monday.

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