Tylenol orders in pregnant women plunged after Trump falsely linked the drug to autism

Tylenol orders in pregnant women plunged after Trump falsely linked the drug to autism

By Sara Novak

On September 22, 2025, President Donald Trump held a briefing at the White House in which he announced that his administration would notify doctors that the use of acetaminophen, the active ingredient in Tylenol, was linked to a “greatly increased risk of autism” – despite evidence to the contrary. Trump instead recommended that pregnant women limit their use of over-the-counter pain and fever relievers only to those times when they couldn’t “tough it out.” During the same briefing, Trump, along with Health and Human Services Secretary Robert F. Kennedy, Jr., recommended without evidence the use of a drug called leucovorin (folinic acid) for the treatment of autism.

In the weeks after Trump’s announcement, the number of pregnant emergency room patients taking acetaminophen (another name for acetaminophen used internationally) dropped by up to 20 percent, according to an analysis published Thursday in Lancet. Researchers did not notice any difference in the number of emergency room orders for the drug in non-pregnant patients.

The study also found that the number of children aged five to 17 who were prescribed leucovorin as an outpatient increased by 71 per cent.

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The researchers included 88,857 pregnant patients and 853,216 non-pregnant patients in the analysis. The findings suggest that the Trump administration’s announcement had a notable effect, although it’s unclear from the data whether orders for acetaminophen changed because of patients refusing pain medication or because doctors made a clinical decision. Experts say it was probably a combination of both.

“Immediately after this press conference, thousands of women who would have had a fever or pain did not get treated, based on false statements and mischaracterizations of data from the White House,” said study co-author Jeremy Faust, an emergency physician at Brigham and Women’s Hospital and an assistant professor at Harvard Medical School.

High-quality studies have shown that acetaminophen is the safest available pain reliever and antipyretic medication to take during pregnancy. Furthermore, untreated fever during pregnancy carries a number of risks to the fetus, including miscarriage, birth defects and premature birth. Fever during pregnancy has also been linked to an increased likelihood of autism in the offspring.

The most consistent study of acetaminophen use during pregnancy and autism rates in children, published in JAMA in 2024, followed almost 2.5 million children in Sweden from 1995 to 2019; it accounted for the genetic risk of autism by comparing siblings. The study found no evidence of an increased likelihood of autism or attention deficit hyperactivity disorder (ADHD) associated with paracetamol use. “In siblings where the mother took acetaminophen during one pregnancy but not during another, the siblings still shared exactly the same autism and ADHD risk,” says Brian Lee, senior author of JAMA study and an epidemiologist at Drexel University.

It is unclear from Lancet investigate whether pregnant patients received another medication or whether they went without it. Nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen and aspirin are not considered safe during pregnancy because they can cause low amniotic fluid and an increased risk of birth defects. And opioids carry a risk of addiction in the pregnant woman and in the baby after birth and can cause withdrawal symptoms in the latter.

As for leucovorin, the drug Trump and his FDA promoted for autism treatment, Lee says studies showing the drug’s effectiveness are “preliminary at best.” The largest study of the drug included only 77 children and was withdrawn in January due to errors in the data analysis.

“Words matter, and patients and practitioners want to be able to trust the guidance that comes from our state institutions,” says Jennifer Braverman, a maternal and fetal medicine physician at the University of Colorado Medicine, who was not involved in the study. She adds that as a result of Trump’s announcement, many pregnant women were either given something less safe or just told to screw up. “It’s very dismissive of women’s pain and suffering,” she says.

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