WHO says no conclusive evidence links acetaminophen use to autism

“Extensive research has been undertaken over the past decade, including large-scale studies, looking into links between acetaminophen use during pregnancy and autism. At this time, no consistent association has been established,” WHO said in a statement.

The agency advised pregnant women to continue following the recommendations of their doctors or health workers, noting that medicines should be used with caution during pregnancy, particularly in the first trimester.

The statement came a day after U.S. President Donald Trump said the Food and Drug Administration (FDA) would soon issue guidance cautioning doctors about Tylenol use in pregnancy, citing what he described as a “very increased risk of autism.”

On Tuesday, the FDA said it had initiated a process to update warning labels on acetaminophen products, including Tylenol, to reflect evidence suggesting possible links between use during pregnancy and neurological conditions such as autism and ADHD in children. The agency also sent a letter alerting physicians nationwide.

“The FDA is taking action to make parents and doctors aware of a considerable body of evidence about potential risks associated with acetaminophen,” Commissioner Marty Makary said. “Even with this body of evidence, the choice still belongs with parents. The precautionary principle may lead many to avoid using acetaminophen during pregnancy, especially since most low-grade fevers don’t require treatment. It remains reasonable, however, for pregnant women to use acetaminophen in certain scenarios.”

Tylenol maker Kenvue said in a statement to the BBC that the science “clearly shows that taking acetaminophen does not cause autism.” The company added: “We strongly disagree with any suggestion otherwise and are deeply concerned with the health risk this poses for expecting mothers.”

The Autism Science Foundation also voiced concern over comments from Trump and U.S. Health and Human Services Secretary Robert F. Kennedy, which suggested that acetaminophen during pregnancy causes autism, that a medicine derived from folate could treat symptoms of autism, and that vaccines should be split across multiple visits, including separating the MMR vaccine into individual shots.