In the past week, the Trump administration spread two pieces of pseudoscience related to autism: first, that acetaminophen use during pregnancy can cause autism, and second, that a prescription supplement called leucovorin (folinic acid) can benefit autistic children.
ELIZABETH JACOBS; [email protected]
Jacobs is a professor emerita of epidemiology at the University of Arizona.
Jacobs told the Institute for Public Accuracy: “At the press conference on Monday [Sept. 22], Trump and [FDA Commissioner] Marty Makary and the rest were clearly stating that using Tylenol during pregnancy causes autism. That’s because a paper that was published last month came to the conclusion that there is a signal that acetaminophen is associated with autism. I read that paper, and there is a line in the paper that says that a ‘causal relationship is plausible.’ That is short of saying that there is a causal relationship. It is possible, but it is unlikely, based on another paper published in 2024 with more than a million kids in it. In that paper, when scientists controlled simultaneously for genes and environment, there was no relationship between acetaminophen and autism.
“What is concerning, of course, is that the evidence is at least as strong that if you have a fever during pregnancy, the fetus is at increased risk for autism. Likewise, there is an association
between infections during pregnancy and autism. So it is deeply problematic to suggest that acetaminophen creates risk.
“On the same day as the press conference, Marty Makary sent out a letter to physicians walking back his and Trump’s claims. In his letter, Makari stated: ‘To be clear, while an association between acetaminophen and autism has been described in many studies, a causal relationship has not been established.’ So what Makari is saying to doctors is not the same as what was said during that press conference. Dr. Oz also walked back his statements. Oz has actually now said that if you have a high fever during pregnancy, you should take Tylenol when appropriate.
“At that same press conference, the administration claimed that leucovorin can improve autism. Leucovorin is an issue because we have been told over and over again by HHS that they want ‘gold standard science.’ But the evidence for using leucovorin for autistic kids is extremely weak. There are only three studies that have looked at this with 154 kids. That is not gold standard science. That is out of usual procedure for the FDA… They are trying to maintain their influence at the expense of giving the public rigorous scientific information.”