Trump Tylenol Warning Triggers Debate Over Autism Risk and Diagnostic Definitions

President Donald Trump told expectant mothers not to take Tylenol or acetaminophen during pregnancy, claiming it could raise the risk of autism in a child. He spoke at a Monday press conference and urged caution, suggesting that mothers should avoid the medication when possible.

Medical researchers quickly pushed back. Dr Allen Frances, a Duke University professor emeritus whose work helped broaden autism's diagnostic criteria, described the warning as absolutely moronic and dangerous, and he criticized the FDA head for supporting the statement, arguing it fed reckless misinformation.

Frances has long argued that the rise in autism rates reflects changes in diagnosis rather than exposure to a single drug or vaccine. He led the expansion of the autism definition in the 1990s, first in 1994 to include Asperger's syndrome and later, in 2013, to label the broader category as autism spectrum disorder. He says the intent was to identify children who were slipping through the cracks and help them access services, but he acknowledges that broader criteria contributed to public debates and conspiracy theories, including anti-vaccine sentiment.

Trump's supporters have cited a 2024 Mount Sinai and Harvard study that reviewed data from 46 prior studies and found an association between acetaminophen exposure during pregnancy and a higher likelihood of neurodevelopmental disorders, including autism. The authors stressed that association is not causation. Dr Brian K. Lee, an epidemiologist at Drexel University and a co-author, said the best science to date indicates that acetaminophen use during pregnancy does not cause autism, noting that several observational studies show only a statistical association.

Other researchers warn against inferring causality from observational data. A 2024 Swedish study analyzing data from more than 2.4 million children found no heightened autism risk linked to acetaminophen exposure. Pediatric neuropsychologist Nechama Sorscher told the Daily Mail that research in this area remains inconclusive and stressed the need for careful, balanced communication that acknowledges uncertainties. Jeff Singer, a senior fellow at the Cato Institute, said the question should be left to scientists and clinicians and noted that fever management during pregnancy sometimes requires acetaminophen.

Tylenol's maker, Kenvue, said acetaminophen remains the safest pain reliever for pregnant women when needed, adding decades of research supports no credible link to autism and backing the conclusions of public health professionals who reviewed the science.

Regulators and researchers emphasize that many drugs taken during pregnancy warrant ongoing study, and that clear, honest communication is essential for families. Frances has warned that while diagnostic expansion aimed to help patients, it may have contributed to misinformation about vaccines and medications. He characterized the definitional changes as a well-intentioned effort with unintended consequences and urged policymakers to rely on solid science rather than sensational signals.

Despite rising autism counts in the United States and elsewhere, experts say much of the increase reflects broader criteria and increased awareness rather than a single exposure. The conversation around acetaminophen and autism remains unsettled, and public health officials advise pregnant women to consult their healthcare providers about medication use, weighing the risks of illness against the benefits of treatment.