Danish Tylenol study

A nationwide Danish study published April 13 found no evidence that taking Tylenol during pregnancy raises a child’s autism risk. (jamanetwork.com) The study used Danish national registers to track more than 1.5 million children born from 1997 to 2022, including 31,098 with prenatal acetaminophen exposure. Reuters reported that 1.8% of exposed children were later diagnosed with autism, versus 3.0% of unexposed children. (jamanetwork.com) (reuters.com) Researchers said the result held after they adjusted for timing of exposure, dose, and family-level factors with sibling comparisons. The paper was led by Kira Philipsen Prahm and colleagues at Copenhagen University Hospital and published in JAMA Pediatrics. (jamanetwork.com) (cidrap.umn.edu) Acetaminophen, sold as Tylenol in the United States and paracetamol in Europe, is one of the few pain and fever drugs widely used in pregnancy. Doctors often avoid ibuprofen and other nonsteroidal anti-inflammatory drugs later in pregnancy because of fetal risks. (jamanetwork.com) (statnews.com) The question has been debated for years because some observational studies found small associations between prenatal acetaminophen use and neurodevelopmental diagnoses. Those studies also struggled with confounding, meaning the underlying reason a pregnant patient took the drug, such as infection, pain, or fever, could be tied to the outcome. (jamanetwork.com) (publichealth.jhu.edu) That debate intensified in January, when a Lancet systematic review of 43 studies found no link between prenatal acetaminophen exposure and autism, attention-deficit/hyperactivity disorder, or intellectual disability after focusing on higher-quality evidence. (statnews.com) (cbsnews.com) The Danish paper also arrived after renewed political attention in the United States. Reuters reported that the Trump administration had urged pregnant women to avoid the drug, while Danish regulators said in September 2025 that their recommendation was unchanged and paracetamol could still be used during pregnancy if needed. (reuters.com) (thelocal.dk) No single observational study can prove a drug never causes harm, and researchers have said the question depends on the total body of evidence rather than one headline result. For now, the newest Danish data add one of the largest registry analyses yet to a 2026 literature review that already found no autism signal. (publichealth.jhu.edu) (jamanetwork.com)