PLoS One

Is opioid use in pregnancy linked to autism or ADHD risk?

September 22, 2025

Study details: A retrospective, population-based cohort study in Sweden analyzed 1,267,978 children (born 2007–2018) for autism spectrum disorder (ASD) and 918,771 children (born through 2015) for attention-deficit/hyperactivity disorder (ADHD), using national register data with follow-up through 2021. Cumulative dose and duration of prescribed opioid analgesic (POA) exposure during pregnancy were derived from filled prescriptions. Multiple analytic strategies including adjustment for measured covariates, comparison with children of parents with pain conditions but no POA use, pre-pregnancy POA exposure, and sibling comparisons were employed to address confounding.

Results: At age 10, cumulative incidence of ASD was 2.0% (unexposed), 2.9% (low-dose POA), and 3.6% (high-dose POA). Unadjusted and covariate-adjusted models showed increased ASD risk with higher POA exposure (e.g., hazard ratio [HR]_high, 1.34, 95% confidence interval [CI], 1.24–1.44). However, these associations were attenuated or eliminated in alternative designs: HR_high, 1.10 (95% CI 1.00–1.21) for pre-pregnancy POA comparison, and HR_high, 0.99 (95% CI 0.81–1.21) in sibling analysis. Similar patterns were observed for ADHD and with exposure duration.

Clinical impact: At typical prescribed doses and durations, the observed associations between prenatal POA exposure and neurodevelopmental disorders are largely attributable to confounding factors rather than a direct teratogenic effect. While a small increased risk with very high exposure cannot be excluded, routine prescribed POA use in pregnancy doesn’t appear to independently increase ASD or ADHD risk.

Source:

Cleary EN, et al. (2025, September 16). PLoS Med. Prescribed opioid analgesic use in pregnancy and risk of neurodevelopmental disorders in children: A retrospective study in Sweden. http://pubmed.ncbi.nlm.nih.gov/40956781/