The current presidential administration has placed significant focus on addressing a cited increase in the rate of autism diagnoses. Late last month, President Trump, alongside the Health Secretary, Robert F. Kennedy Jr., issued new health guidance and announced in a press conference that there is evidence of a link between the use of acetaminophen during pregnancy and neurological effects, specifically autism and attention-deficit/hyperactivity disorder (ADHD), in children post-birth. The announcement was coupled with a notice from the U.S. Food and Drug Administration (FDA) that it plans to initiate a process for a label change on acetaminophen products to inform consumers of the link, as well as a letter issued by the FDA to physicians about the potential link. The FDA’s letter specifies that “a causal relationship has not been established” between use of the medication and autism, while also asserting that clinicians may want to suggest pregnant people reduce their use of the medication. The issuance of sweeping advice from the Trump Administration in light of these inconsistencies is unsettling from a public health perspective because acetaminophen remains the recommended drug for fever reduction in pregnant people. The guidance to minimize acetaminophen use could be harmful for pregnant people because it may lead them to endure unnecessary pain and fever, which are dangerous for the pregnant person and the fetus.
In addition, mixed messages have created confusion in the legal context because of the announcement’s reliance on a study that was previously found inadmissible by a judge. In 2022, a group of families sued the maker of Tylenol, an acetaminophen product, for failure to warn consumers of the risk that prenatal exposure to the medication may create a heightened risk of autism. One of the experts used to support the families’ proposition was Andrea Baccarelli, MD, PhD, who was also cited in the Trump Administration’s recent announcement. The judge rejected this expert, as well as all of the families’ other experts, in an order in 2023, stating that the experts had “cherry-picked” data in their analyses. The case was subsequently dismissed in 2024, and the dismissal is currently on appeal.
In light of the executive branch’s reliance on one of the same experts as the families, the plaintiffs’ attorney has filed a letter with the court in support of their appeal, noting that the expert had been relied upon in the conclusions of a recent White House briefing. The lawyer notes the separation of power concerns that would arise if the ruling that this expert’s opinions are inadmissible in court is affirmed, while the opinions are simultaneously cited as valid by the executive branch. On the other hand, the attorney for Tylenol in the same lawsuit has also filed his own letter referencing the advice put out by the Trump administration as support of the defendant’s position that they have not failed to include any warning of a link to autism on their products. The defendant’s lawyer cites the language in the FDA’s letter to doctors stating that there is no causal relationship between the drug and autism. In light of each of letters, the judge has pushed back oral argument on this appeal that was set to occur on October 6, 2025 to November 17, 2025.
The use of the Trump administration’s guidance in this litigation to both support and disprove a link between Tylenol and autism emphasizes the confusion the new health guidance has created. What does this mean going forward? In the immediate future, the guidance may create fear among pregnant people about treating their pain and fever during pregnancy. If moving forward, the guidance does successfully ignite litigation aimed at a requirement to label acetaminophen products as not recommended during pregnancy, it could lead to an increase in pregnant people leaving pain and fever untreated during pregnancy, potentially putting them in danger of other complications.