Overview
- The Danish cohort study, published Monday in JAMA Pediatrics, examined more than 1.5 million singleton births from 1997 to 2022 using national prescription records.
- Researchers reported no significant association with autism in the general population (hazard ratio about 1.03) and no signal in a within-family sibling analysis (hazard ratio about 1.09).
- Among 31,098 children with documented prenatal prescriptions, 1.8% were later diagnosed with autism compared with 3.0% among unexposed children after adjustments for confounding factors.
- The analysis did not capture over-the-counter acetaminophen purchases, which the authors noted as a key limitation because most users obtain Tylenol without a prescription.
- At a House hearing Friday, Health Secretary Robert F. Kennedy Jr. dismissed the study as “garbage,” even as medical groups continue to recommend acetaminophen for fever and pain in pregnancy and the FDA’s 2025 label review remains under consideration.