Texas Sues Tylenol Makers, Claiming They Hid Autism Risks

[GreatGazoo]

66. Seheult details the biological mechanisms by which ASD and other neurological

disorders can arise during pregnancy. He includes studies that found no correlation, studies with negative correlation and studies with positive correlation.

Correlation is, of course, not causation and Seheult goes through the proposed mechanisms (causation) by which acetaminophen can contribute to the development of ASD. He cites meta analysis (a study of studies, the gold standard) which incorporates the study you mention. The meta analysis was done by Diddier Prada, Beate Ritz, Ann Z. Bauer & Andrea A. Baccarelli and includes the 2.5 million of the smaller study.

The meta analysis was reprinted by Harvard and other major health institutions:
https://hsph.harvard.edu/news/using-acetaminophen-during-pregnancy-may-increase-childrens-autism-and-adhd-risk/

The lengthy study is summarized by the authors as follows:

Results

We identified 46 studies for inclusion in our analysis. Of these, 27 studies reported positive associations (significant links to NDDs), 9 showed null associations (no significant link), and 4 indicated negative associations (protective effects). Higher-quality studies were more likely to show positive associations. Overall, the majority of the studies reported positive associations of prenatal acetaminophen use with ADHD, ASD, or NDDs in offspring, with risk-of-bias and strength-of-evidence ratings informing the overall synthesis.

Conclusions

Our analyses using the Navigation Guide thus support evidence consistent with an association between acetaminophen exposure during pregnancy and increased incidence of NDDs. Appropriate and immediate steps should be taken to advise pregnant women to limit acetaminophen consumption to protect their offspring’s neurodevelopment.

Peer reviews are linked from the study (right under conclusions )

https://ehjournal.biomedcentral.com/articles/10.1186/s12940-025-01208-0


ETA: Current science is not saying that Tylenol causes ASD directly, nor that Tylenol use is the only way that ASD begins. Only that its use should be limited during pregnancy and that safer alternatives should be developed.