The Association Between In Utero Exposure to Painkillers and Trajectories of Hyperactivity and Emotional Problems in Children with Autism Compared with Neurotypical Peers

Background/Objectives: In utero exposure to painkillers has raised concerns regarding its potential impact on neurodevelopmental disorders, such as autism spectrum disorder (ASD). This study investigates the association between in utero exposure to painkillers and trajectories of hyperactivity and emotional problems in children with and without ASD, separately. Methods: Data were drawn from 5107 participants enrolled in the Longitudinal Study of Australian Children. Emotional and behavioral problems were assessed using the Strengths and Difficulties Questionnaire at ages 4, 6, and 8 years. ASD diagnosis was determined based on parental self-report by age 12. To examine the association between the exposure and the outcomes, mixed linear models were applied to assess the impact of in utero exposure to painkillers on hyperactivity and emotional problems, controlling for sex, time, and other perinatal risk factors. The interaction term between exposure and time was included to evaluate the effect of exposure on the trajectory over time. Results: In utero exposure to painkillers did not significantly affect hyperactivity or emotional problem trajectories in children with ASD. However, in non-ASD children, painkiller exposure was associated with worsening emotional problems by age 8, with males being affected to a greater extent than females. Further, emotional problem scores increased over time by gender, reflecting developmental challenges in early childhood. Conclusions: These findings indicate that prenatal painkiller exposure is unlikely to be a major determinant of the severity of neurodevelopmental outcomes in autistic children, but its role in neurodevelopmental outcomes among neurotypical children warrants further investigation. Future research should prioritize precise exposure assessments and integrate multi-environment interactions to further elucidate the long-term impacts of prenatal painkiller use.