Another New Large Study Proved No Link Found Between Tylenol Use During Pregnancy and Autism

The claims brought to the agenda by US Secretary of Health Robert F. Kennedy Jr. and former President Donald Trump have recently caused a serious debate on public health. While Kennedy promised to find the root cause of autism by September, Trump suggested that autism must be based on an extrinsic environmental cause. These unfounded claims have turned into a false narrative that pregnant women using Tylenol (paracetamol) as a painkiller causes autism. Such statements are not only derogatory to individuals on the autism spectrum but also lack any scientific basis. However, these environmental factor narratives have caused unnecessary panic among the public and a tendency to refrain from using medication.

Contrary to these claims, there is no scientific evidence of any causal link between Tylenol use during pregnancy and autism. Despite this, some groups that place excessive trust in these government statements have started to avoid using painkillers. In fact, some figures, such as Texas Attorney General Ken Paxton, have made a mockery of themselves on a national level with the lawsuits they filed against Kenvue, the manufacturer of Tylenol. The public pressure arising after these statements has grown so much that ultimately even RFK Jr. had to admit that there is no proven causal link regarding the issue. Nevertheless, scientists continue their high-quality and comprehensive scientific research to eliminate the damage caused by this misinformation.

A new and comprehensive study published in the journal JAMA Internal Medicine has once again debunked the myth between Tylenol and autism. In this comprehensive study, researchers meticulously examined the electronic health records of over 700.000 mother-child pairs in Hong Kong between 2001 and 2023. In approximately 43 percent of these mother-child pairs, it was determined that the children were exposed to acetaminophen (the active ingredient of Tylenol) in the womb. Scientists stated that they could see absolutely no connection between prenatal paracetamol use and autism or ADHD (Attention Deficit Hyperactivity Disorder). The study clearly demonstrated that the dosage taken, the trimester of pregnancy when the medication was used, the frequency of use, or the mother's age did not change this result.

As frequently seen in some previous studies and the claims of figures like RFK Jr., it is possible to obtain a superficial correlation (link) if the sibling-matched analysis method is set aside. However, this time researchers applied a "negative control" analysis to examine the situation more deeply and observed that the relationship in question completely disappeared. In the negative control analysis, scientists compared the data based on whether mothers used paracetamol before pregnancy or after giving birth. A similar statistical relationship with an autism diagnosis in children emerged when the mother took the medication previously or afterwards, but researchers evaluated this as a "biologically impossible" scenario. This situation proves that the observed link stems from various external factors rather than a true cause-and-effect relationship.

All these scientific data reveal the crucial difference between correlation and causality. Researchers state that the relationship seen between the mother's Tylenol intake and the child's autism status may actually be a result of familial, genetic, or environmental factors. In other words, Tylenol use does not cause autism; on the contrary, it may be associated with familial predispositions or environmental stress factors that could trigger both conditions. Contrary to what Trump and Kennedy have tried to convince people, these statistical clues do not show that the drug is guilty, but merely point to a complex underlying picture. Consequently, to make healthy decisions and avoid unnecessary fears, it is of great importance to rely on scientific methods that have been repeatedly tested for accuracy, rather than the political rhetoric of authorities.