Harvard sees a potential link, hell it’s the name of the paper: “Using acetaminophen during pregnancy may increase children’s autism and ADHD risk ”.
I think that it might be a real thing is because nobody really knows how acetaminophen even works. All the theories involve influencing the brain‘s chemistry. Who knows, maybe influencing a fetus’s brain chemistry can be bad.
https://hsph.harvard.edu/news/using-acetaminophen-during-pre...