US to study link between pregnant women taking Tylenol and autism in newborns

The Wall Street Journal learned of HHS's plans. After the story was published, shares of Kenvue, the company that makes Tylenol, fell by 9.3%. The company was spun off from Johnson & Johnson (J&J) in 2023, and Tylenol was first produced in 1955 by McNeil Laboratories, which was later acquired by J&J. In 1960, the drug became available over the counter.

Tylenol, which contains the painkiller acetaminophen, is widely used in the United States, including by pregnant women. Kenvue expressed hope that there is no cause-and-effect relationship between acetaminophen use during pregnancy and autism in newborns. Christopher Zahn, clinical director of the American College of Obstetricians and Gynecologists (ACOG), said pregnant women should not be afraid of acetaminophen, as it is safe and one of the few pain-relief options available to pregnant women. It is estimated that more than 60% of pregnant women in the United States use acetaminophen for headaches and other conditions.

Secretary of Health Kennedy Jr. himself called any statements about the risk of autism due to acetaminophen before the official report was released speculation. He emphasized that the department uses the most advanced scientific data to explain the reasons for the unprecedented increase in autism in the United States.

According to the U.S. Centers for Disease Control and Prevention (CDC), one in 31 children aged eight will be diagnosed with autism in 2022 (32.2 per 1,000 children). The first reason for this statistic is that the definition of autism has been expanded, making it easier for more people to qualify for a diagnosis, said Wendy Clagg, associate director of the Johns Hopkins Autism Center. The second factor is greater awareness and acceptance of the condition, making people more comfortable seeking help and disclosing their diagnosis.

In 2024, a study was published in the Journal of the American Medical Association (JAMA) involving more than 2 million children born in Sweden from 1995 to 2019. Of these, about 185,000 were born to mothers who took acetaminophen during pregnancy. The researchers compared the autism rates of these children with their siblings, as well as with children whose mothers did not take the drug. As a result, the scientists found no link between autism, attention deficit disorder, or other neurodevelopmental disorders and the use of the painkiller.

In August 2025, the results of 46 studies were published in the journal BMC Environmental Health, six of which were related to the topic of acetaminophen and autism. Experts confirmed the effect of acetaminophen on the risk of developing a nervous system disorder due to possible negative early exposure to chemical, toxic, and pharmacological substances.

The U.S. Food and Drug Administration (FDA) also addressed these risks in 2015 and recommended that pregnant women always consult with their doctors before taking any medication. Following the WSJ article, the Autism Science Foundation called the autism-acetaminophen link limited and controversial, but supported research into the cause of the disorder.

Tylenol is known not only as a popular fever-reducing and pain-relieving drug, but also as a drug that killed six people in 1982. Then, Extra-Strength Tylenol capsules were poisoned with potassium cyanide by an unknown assailant. The high-profile incident was called the "Chicago poisonings." And in 2008 and 2015, J&J's McNeil Consumer Healthcare division recalled batches due to contamination of the drug with heavy metals. However, despite all the stories about contamination, Tylenol remains the leading drug among over-the-counter fever-reducing and pain-relieving drugs on the U.S. market.

In December 2022, Tylenol was mentioned in the media again. American doctors demanded that the FDA remove Tylenol from sale along with Theraflu due to its ineffectiveness in combating nasal congestion.