Pregnant ER patients took less Tylenol after Trump's autism claims: study

After a September 2025 press conference in which President Trump told pregnant women not to use Tylenol, usage dropped in ERs, a new study found.

President Donald Trump's statements in September about Tylenol use during pregnancy and autism have likely had a real-world impact despite experts and years of evidence disproving any link, according to a new study.

After a Sept. 22 White House briefing, in which Trump, Secretary of Health and Human Services Robert F. Kennedy Jr. and other officials said they had found an "answer to autism" and told pregnant women to avoid taking Tylenol (the brand name for acetaminophen or paracetamol), emergency room orders for the drug took a noticeable downturn, according to research published March 5 in the medical journal The Lancet.

The study found that the use of acetaminophen to treat pregnant patients decreased by 10% in the months that followed the briefing, which attributed an increased risk of autism to Tylenol use during pregnancy, with limited evidence. There was no change in usage, however, for women of the same age who were not pregnant.

This noticeable downward trend in Tylenol orders began as quickly as the day after the conference, according to study co-author Dr. Michael Barnett, professor of health services, policy and practice at the Brown University School of Public Health.

"The rapidity of the response was surprising to us," he told USA TODAY. "Public officials’ words have power, and both the public and their clinicians shifted behavior immediately."