The use of Tylenol by women during pregnancy was not ‌associated with autism in their children, according to results of a nationwide study in Denmark published on Monday.

Among more than 1.5 million children born between 1997 and 2022, including 31,098 exposed to Tylenol in the womb, autism was later diagnosed in 1.8% of ‌exposed children and 3% of the unexposed group, Danish researchers ​reported in JAMA Pediatrics.

The lack of an association persisted after researchers accounted for individual risk factors including the dose of ⁠the drug and the trimester of pregnancy in which it was used, ​the report said.

A 2024 Swedish study also found no link between autism ⁠and pregnancy use of Tylenol, a brand name for acetaminophen and paracetamol.

A 2025 review by U.S. researchers of 46 earlier studies did suggest a possible link between prenatal acetaminophen exposure and neurodevelopmental ‌disorders such as autism and attention deficit hyperactivity disorder in children, ​but the researchers said ‌the study does not prove the drug caused those conditions. They advised that pregnant women should ‌continue to use acetaminophen as needed, at the lowest possible dose and for the shortest possible period.

In September, the U.S. Food and Drug Administration said ⁠it was initiating the process for ‌a label change for ⁠acetaminophen to warn that its use by pregnant women may be associated with an increased risk ⁠of autism ⁠and ADHD.

At the time of the FDA announcement, U.S. President Donald Trump said pregnant women and infants ‌should not take the drug because of its link with autism.

Since then, national and international medical groups have decried the president's comments, saying they were not evidence-based.

A ‌month after ​the FDA said it ‌would recommend limiting Tylenol use in pregnancy, U.S. Health Secretary Robert F. Kennedy, Jr. said evidence does not show that Tylenol definitively causes ​autism but that it should still be used cautiously.

The FDA declined to comment on the status of its planned label change.