A large study spanning more than two decades has found no association between paracetamol (acetaminophen) use during pregnancy and the risk of autism or attention-deficit/hyperactivity disorder (ADHD) in children. The findings were published in JAMA Internal Medicine.
Researchers analysed electronic health records from Hong Kong covering 2001 to 2023, including more than 700,000 mother and child pairs. Approximately 43% of children were exposed to paracetamol in utero. The study used sibling comparisons, examining pairs where one sibling was exposed to the medication during pregnancy and another was not.
This approach accounts for the substantial genetic component of both autism and ADHD. If paracetamol were a contributing factor, researchers would expect differences between exposed and unexposed siblings. The study found none.
The autism analysis included more than 124,000 children followed for at least two years, whilst the ADHD component involved over 97,000 children followed for at least five years. No association was found regardless of trimester, prescribed dose, or recommended frequency of use.
The Hong Kong study joins similar research from Sweden and Japan, both of which used sibling comparison methods and reported no link between prenatal paracetamol exposure and neurodevelopmental disorders.
Paracetamol remains the first choice for fever and pain relief during pregnancy according to the American College of Obstetricians and Gynecologists. The medication is considered the safest option when treatment is needed, though, as with all drugs during pregnancy, use should follow medical guidance.
The growing body of evidence from multiple countries using robust methodological approaches provides reassurance regarding the safety of paracetamol use during pregnancy.
Source: Science News / JAMA Internal Medicine (2026)
