Key Findings:
- A new study from the University of Washington found that maternal acetaminophen (APAP) exposure during pregnancy was linked to a 3.15 times higher risk of ADHD in children by ages 8-10.
- Female children showed a stronger association, with a 6.16 times higher risk of ADHD when APAP biomarkers were present in maternal blood.
- Researchers identified changes in placental gene expression, including increased IGHG1 gene activity, which may partly mediate the link between APAP exposure and ADHD.
The study, published in Nature Mental Health, analyzed blood samples from 307 African American mother-child pairs in the Conditions Affecting Neurocognitive Development and Learning in Early Childhood (CANDLE) cohort. Researchers used untargeted metabolomics to detect APAP metabolites in second-trimester plasma samples.
Children exposed to maternal APAP in utero had a significantly higher risk of ADHD diagnoses. The effect was stronger in female children, who showed both increased ADHD risk and gene expression changes in immune-related pathways. The study also found downregulation of oxidative phosphorylation pathways in both sexes, a pattern linked to neurodevelopmental impairment.
The findings provide strong evidence connecting prenatal acetaminophen exposure to ADHD risk and offer insights into the potential molecular pathways driving this link. While acetaminophen is widely considered safe for use during pregnancy, this research emphasizes the need for further investigation and careful consideration of its risks.
Source:
Jackson, J., et al. (2025). Associations of Maternal Blood Biomarkers of Prenatal APAP Exposure With Placental Gene Expression and Child Attention Deficit Hyperactivity Disorder. Nature Mental Health.