United States President Donald Trump recently claimed that using the common painkiller acetaminophen (also known as paracetamol and by the brand name Tylenol in the US) during pregnancy is fuelling the rise in autism diagnoses. He then went on to suggest pregnant women should “tough it out” rather than use the common painkiller if they experience fever or pain. This announcement has caused alarm and confusion worldwide. But despite Trump’s claim, there is no strong scientific evidence to back it up. Our study of nearly 2.5 million births in Sweden published in 2024 shows no evidence that acetaminophen use during pregnancy increases a child’s risk of autism. This is the largest study conducted on the subject to date.