A large study published in JAMA Internal Medicine has found no evidence that taking paracetamol (acetaminophen, commonly sold as Tylenol) during pregnancy increases the risk of autism or ADHD in children. The research analyzed electronic health records from more than 700,000 mother-child pairs in Hong Kong between 2001 and 2023. It directly challenges claims previously made by President Donald Trump and Health and Human Services Secretary Robert F. Kennedy Jr. linking acetaminophen use during pregnancy to autism.
What did the study find?
Researchers found that children exposed to paracetamol in the womb were no more likely to develop autism or ADHD than children who were not exposed.
To strengthen the findings, the study used a sibling comparison design, looking at families where one child was exposed during pregnancy and another was not. Even in these comparisons, there was no difference in autism or ADHD rates, suggesting no link between the medication and either condition.
The autism analysis included more than 124,000 sibling-matched children, while the ADHD analysis included more than 97,000.
Why this is important
Trump and RFK Jr have repeatedly raised concerns about acetaminophen use during pregnancy and its possible connection to autism. However, researchers say the new findings add to a growing body of evidence that does not support those claims.
The study also notes that earlier associations seen in some research may have been influenced by other factors, such as genetics, family environment or the medical conditions that led to medication use during pregnancy.
The results remained consistent regardless of dosage, timing of exposure, trimester or maternal age.
What does this mean?
Medical experts quoted in the broader research context say acetaminophen remains one of the most widely recommended options for treating pain and fever during pregnancy.
They also emphasize that avoiding necessary treatment can carry risks. Untreated fever during pregnancy has been linked to complications including preterm birth and miscarriage.
Current evidence does not support avoiding clinically indicated acetaminophen use due to concerns about autism or ADHD.
The bigger picture
The findings match a major 2024 study involving nearly 2.5 million children, which also found no evidence of a causal link between prenatal acetaminophen use and autism or ADHD after accounting for family-related factors.
Taken together, the studies reinforce that earlier reported associations do not hold once genetic and environmental influences are properly controlled for.
