Experts caution against simple link between paracetamol use in pregnancy and autism as Trump touts review

A political controversy over autism risk factors erupted again after President Donald Trump touted a government review he said identified a link between maternal paracetamol use during pregnancy and autism. The review, led by health secretary Robert F. Kennedy Jr., has been framed by its proponents as pointing to an environmental contributor. Scientists and clinicians, however, cautioned that autism is a highly complex neurodevelopmental condition with a substantial genetic component and that a single exposure is unlikely to explain the full spectrum of cases.

Paracetamol, a widely used pain reliever sold as Panadol in the United Kingdom and Tylenol in the United States, is commonly used by pregnant women for fever, headaches and pain relief. It remains the NHS’s first-choice analgesic for short-term use at the lowest effective dose during pregnancy. In the United Kingdom, about half of pregnant women report using paracetamol at some point, while U.S. estimates hover around two-thirds of new mothers. While some studies have suggested an association between parental or fetal exposure to paracetamol and autism, experts emphasize that correlation does not prove causation and that multiple factors are involved.

In August, a review of varied studies led Harvard scientists to conclude there was some evidence of an association between paracetamol use in pregnancy and autism; however, they noted that maternal health problems and other confounding factors were also linked to autism and cautioned against drawing a causal line. Other large analyses have yielded mixed results. A 2024 Swedish study involving 2.4 million children, led by researchers at Karolinska Institute, found no association between paracetamol exposure in pregnancy and the child’s risk of autism. Experts say that such discrepancies underscore the risk of over-interpreting a single exposure against a condition as multifaceted as autism.

Autism is widely understood to be highly heritable. To date, more than 800 genes have been identified as associated with autism, reflecting its genetic complexity. Researchers note that there is no single cause and that the condition can manifest across a broad range of behaviors and abilities. The notion that a handful of environmental exposures could neatly explain rising prevalence is inconsistent with genetic data accumulated through large-scale studies and genome sequencing efforts. Still, the public discussion surrounding environmental factors persists, in part because autism prevalence has risen markedly over recent decades as diagnostic criteria broadened and awareness increased. In the United States, current estimates place autism at about one in 36 children, and in the United Kingdom at roughly one in 57.

The debate has reignited conversations about other environmental considerations, including maternal health, parental age, and exposure to medications such as sodium valproate, which have shown associations with autism in some studies. Some public health researchers caution that even where associations exist, they do not establish causality and that preventing fever or pain during pregnancy requires careful management to avoid potential risks to mother and fetus. Advocates for affected families stress that parents should not be blamed for their child’s diagnosis and emphasize that the focus should remain on supporting early intervention and access to services.

Gina Rippon, a professor emeritus of cognitive neuroimaging, has argued that it is dangerous to frame paracetamol as a sole cause of autism. In an interview, she noted that autism is not a single condition and that there are many contributing factors, including a strong genetic component. Rippon pointed out that more than 800 autism-associated genes have been identified and that the condition has long been understood to run in families, underscoring the limitations of attributing complex neurodevelopmental outcomes to a single medication. The professor added that reducing medical guidance for fear of stigmatizing mothers could have harmful consequences, including the danger of leaving fever or pain untreated during pregnancy.

The conversation around paracetamol and autism is part of a broader, ongoing effort to untangle the factors that shape neurodevelopment. While environmental exposures may play a role in some cases, experts emphasize that much of the risk appears to be inherited and that the increasing prevalence over time reflects a combination of genetics, diagnostic practices, and awareness. As researchers press forward with advances in genetics and large-scale studies, consensus remains that autism results from multiple interacting influences rather than a single, identifiable cause.

In sum, the current scientific landscape does not support a simple causal link between paracetamol use in pregnancy and autism. Researchers stress the importance of guided medical advice on medication use during pregnancy, continued investment in genetics research, and a balanced public health message that avoids stigmatizing mothers while acknowledging the condition’s complexity and heritability. The public discourse surrounding autism, including high-profile claims, should be anchored in rigor, with emphasis on early intervention and support for families.