Exposure of the fetus to paracetamol—a commonly used pain reliever and fever reducer—may be linked to an increased risk of neurodevelopmental disorders in children, including autism spectrum disorders and ADHD. These are the conclusions from research published in the journal Environmental Health. 

Paracetamol (also known as acetaminophen) has long been considered the safest drug of its kind and is widely used by pregnant women—estimates indicate that more than half of pregnant women worldwide take the medication. However, the latest analyses challenge this view and point to the need for caution in its use. 

A team of scientists from the Icahn School of Medicine at Mount Sinai in New York, the University of California in Los Angeles, the University of Massachusetts Lowell, and Harvard University in Boston conducted a meta-analysis of 46 studies involving more than 100,000 participants from different countries. The researchers used the Navigation Guide Systematic Review methodology, considered the gold standard for evaluating the impacts of environmental factors on human health. 

The results show that 27 analyses demonstrated a significant association between paracetamol use during pregnancy and the risk of neurodevelopmental disorders in offspring. The authors emphasize that paracetamol easily crosses the placenta and may trigger oxidative stress in the fetus, disrupt hormonal balance, and cause epigenetic changes affecting brain development. Although the studies do not definitively prove that the drug directly causes these disorders, they highlight the need to reconsider current clinical practices. 

The researchers urge that paracetamol during pregnancy be used only when necessary, for the shortest possible duration, and under medical supervision. They also stress the importance of updating clinical guidelines and continuing research into safe alternatives for treating pain and fever in pregnant women.