A new systematic review and meta-analysis in The Lancet Obstetrics, Gynaecology, & Women’s Health analysing 43 studies finds no link between paracetamol use in pregnancy and increased risk of autism, ADHD, or intellectual disabilities.  

The All Ireland Science Media Centre asked experts to comment.

Dr. Jeffrey Glennon, Assistant Professor at University College Dublin School of Medicine / Conway Institute, comments:

“ADHD and autism affects around 1% and 5% of people in Ireland. There were previous media reports that use of paracetamol (also known as acetaminophen) during pregnancy may constitute a risk factor for ADHD and autism. This is incorrect. A landmark systematic review from Italian, UK and Norwegian researchers published in The Lancet – Obstetrics, Gynecology and Women’s Health analysing 43 studies has concluded there is no association between paracetamol use by expectant mothers and ADHD, autism or intellectual disability in their offspring.

“Moreover this study also performed a meta-analysis aggregating 17 studies and reached the same conclusion. The degree of rigour and the approach taken accounting for any biases in any previous studies was commendable. This reinforces the findings from an earlier Swedish and American study that also demonstrated no link between paracetamol use by pregnant mothers and autism spectrum traits in their children. This study examined registry data for 2.4 million Swedish-born children between 1995 and 2019, analysing data from nearly 186,000 children whose mothers were treated with paracetamol during pregnancy. No evidence of a link between maternal paracetamol use and autistic traits was found. Taken together, the consensus amongst the biomedical community highlights that paracetamol use during pregnancy is safe and expectant mothers should not be concerned over its use affecting their risk of ADHD, autism or intellectual disability in their children.”

Declaration of interest: “I have no conflicts of interest”

Dr Brian Cleary, Irish Medicines in Pregnancy Service & Pharmacy Executive Manager, Rotunda Hospital/ Honorary Clinical Professor-, RCSI, comments: 

“This important systematic review and meta-analysis published in The Lancet Obstetrics, Gynaecology & Women’s Health finds no evidence that paracetamol use during pregnancy increases the risk of autism, ADHD, or intellectual disability in children.

“The authors followed a pre-specified, registered protocol and conducted a robust analysis of all relevant high-quality studies on this topic. In total, 43 studies were reviewed, and 17 were included in the combined meta-analysis.

“The analyses found no increased risk of neurodevelopmental disorders linked to prenatal paracetamol exposure. The results are strengthened by the fact that the authors looked at studies with the most rigorous study design (large sibling-comparison cohorts) and those rated highest for methodological quality.

“This is a very important study as paracetamol is the most widely used medicine to treat pain and fever during pregnancy. This robust review provides reassurance for the public and health professionals: paracetamol remains a safe and effective option for managing pain and fever in pregnancy. Paracetamol is the medication of choice in pregnancy as it is not associated with the adverse effects that can happen with other medicines like ibuprofen or oxycodone. Avoiding paracetamol unnecessarily could lead to risks from untreated fever or severe pain leading to adverse pregnancy outcomes.

“The findings align with position statements from multiple medical organisations including the American College of Obstetricians & Gynecologists, the Royal College of Obstetricians & Gynaecologists, the European Network of Teratology Information Services and international medication regulators.

“This was an unfunded study and the authors reported no conflicts of interest, in contrast to some previous studies in this context where authors were involved in legal processes involving manufacturers of paracetamol.”

Declaration of interest: None