Paracetamol, known as Tylenol in the United States, is safe to use during pregnancy, European researchers have concluded, dismissing claims of a link to autism made last year by U.S. President Donald Trump.
In a review published in The Lancet Obstetrics, Gynaecology & Women’s Health, the researchers said they examined the highest-quality evidence available to address concerns about the drug’s safety. Lead author Asma Khalil, professor of obstetrics and maternal foetal medicine at City St George’s, University of London, said the findings were clear.
“Paracetamol is safe to use in pregnancy,” Khalil said. “The key message is reassurance: when used as recommended, the best available evidence does not support a causal link with autism, ADHD or intellectual disability.”
Khalil said many patients raised concerns after Trump warned pregnant women in September not to take the medication. At the time, national and international medical bodies criticised his comments, saying they were not based on scientific evidence.
Paracetamol, also known as acetaminophen, is currently the only pain reliever considered safe for pregnant women. Doctors already advise using the lowest effective dose for the shortest possible time to treat pain and fever, as leaving these conditions untreated can be risky for both mother and baby.
The research team carried out a systematic review and meta-analysis of existing data, identifying 43 studies that were assessed for quality and potential bias. They paid special attention to studies comparing siblings born to the same mother who used paracetamol in one pregnancy but not in another, helping control for shared genetic and environmental factors.
Only three studies met this strict criterion, but they included more than 260,000 children assessed for autism, and about 335,000 and 405,000 children evaluated for ADHD and intellectual disability respectively.
The results showed no significant link between paracetamol use during pregnancy and any of the conditions studied. The same conclusion held when data from all high-quality studies were combined.
Khalil said earlier research suggesting a possible connection was often affected by bias or confounding factors, including a review of 46 studies cited by Trump officials.
Grainne McAlonan, professor of translational neuroscience at King’s College London, who was not involved in the research, welcomed the findings, saying: “I hope the findings of this study bring the matter to a close.”
