Prenatal paracetamol linked to autism in new US review, prompting caution

A federal review into rising autism rates has amplified attention on prenatal paracetamol exposure after reports that President Donald Trump is expected to announce a link between the drug taken during pregnancy and autism. Paracetamol, known in the United States as acetaminophen and sold as Tylenol and Panadol, is widely used by pregnant women to treat pain, fever or headaches, and health authorities say it should be used for the shortest possible time and at the lowest effective dose.

US researchers from Mount Sinai and Harvard's School of Public Health analyzed data from more than 100,000 people across 46 studies and found strong evidence of an association between prenatal acetaminophen exposure and increased risk of autism and ADHD in children. They caution that the findings do not prove causation, but note the association is robust enough to warrant further study and careful discussion with healthcare providers. The study, published in Environmental Health, urges using the lowest effective dose for the shortest possible duration and to consider non-drug options when appropriate.

Dr. Diddier Prada, assistant professor of population health science at Mount Sinai Hospital and co-author of the study, said higher-quality studies are more likely to show a link between prenatal acetaminophen exposure and risks of autism and ADHD. He added that, given widespread use, even a small increase in risk could have major public health implications, though urged pregnant women not to stop taking medication without medical advice because untreated fever or pain can harm the fetus.

Earlier work includes a 2021 European analysis involving more than 70,000 children across six countries, including the UK, which found that over half of mothers of children with autism or ADHD had used paracetamol in pregnancy. Yet experts warn that findings have been inconsistent; some studies report associations that are not replicated and do not prove causation. Professor Andrew Whitehouse of The Kids Research Institute in Australia noted that autism is multifactorial and that balancing potential risk against the dangers of untreated fever or pain is essential.

Health systems also note rising diagnoses and treatments for ADHD and autism. NHS data show increasing ADHD medication prescriptions in England, with more than 230,000 people prescribed ADHD meds; the UK has seen a rise in ADHD diagnoses, driven by adults as well as children. In the US, Centers for Disease Control and Prevention data show autism diagnoses have risen from about 1 in 150 children in 2000 to about 1 in 31 by 2020. A 2024 study of 12.2 million Americans' health records documented a 175% increase in autism diagnoses over 11 years, fueling ongoing debate about screening, diagnosis criteria and potential contributing factors.

Medical experts emphasize that paracetamol remains an important option for many pregnant women, and the focus should be on the safest approach through consultation with healthcare providers. They urge weighing the risks of fever and pain against potential concerns about neurodevelopment, and consider non-drug measures when possible. The president's reported plan to announce a link comes as part of broader discussions about how evolving science is interpreted and communicated in neurodevelopmental disorders.

Experts caution that current evidence shows association, not causation, and that autism is present from birth and influenced by a combination of genetic and environmental factors. They stress the need for further robust research to clarify the relationship and for clear public health guidance that protects both maternal health and fetal development.