Brief Report: Maternal Opioid Prescription from Preconception Through Pregnancy and the Odds of Autism Spectrum Disorder and Autism Features in Children.

This was an observational case-control study, so it cannot show that opioid prescriptions caused autism or autism features. Only 7.7% of mothers had an opioid prescription, and the authors said the analyses were likely underpowered, with wide uncertainty and a risk of missing a true effect. The study used prescriptions recorded in prenatal medical records, not information about whether the medication was taken, dosage, duration, or reason for prescription. Mothers often did not report specific medication names, so reported conditions such as migraine, injury, back pain, or cough could not be linked to the opioid. The sample had higher socioeconomic status than some other studies, and the opioid prescription rate was lower than rates reported elsewhere, so findings may not apply to other populations. Other unmeasured family factors and the way cases and controls were selected could have affected the results, and smoking during pregnancy was much higher in the autism groups than in population controls. Some analyses grouped autism with developmental delay plus autism features, so the study cannot clearly separate autism-specific findings from broader developmental delay.

The authors reported no conflicts of interest.

Do not read this as proof that maternal opioid prescriptions cause autism. The study found an association only before conception. During pregnancy, the associations were not clear, and the study did not know whether prescriptions were taken, at what dose, or for what reason.