Is Tylenol Safe in Pregnancy? New Study Highlights Potential Risks

The researchers analyzed 46 studies from multiple countries involving over 100,000 participants. Acetaminophen, also known as Tylenol in the US and paracetamol elsewhere, is the most widely used over-the-counter drug by pregnant women worldwide due to its safety record. However, the new findings challenge this view.

Using the Navigation Guide approach, which assesses the quality and potential bias of studies, the team found that higher-quality research was more likely to link prenatal acetaminophen use with increased risks of autism and ADHD.

Scientists explained that acetaminophen can cross the placenta and potentially influence fetal brain development by causing oxidative stress, hormonal disruptions, and epigenetic changes.

Though the study stops short of proving direct cause and effect, it urges caution. Pregnant women should use acetaminophen only under medical supervision and only when necessary because untreated pain or fever can also harm fetal health.

Dr. Diddier Prada, the study’s lead author, emphasized the importance of discussing any medication with healthcare providers. The findings highlighted the need for updated clinical guidelines, safer alternatives for pain management during pregnancy, and further research to better understand these risks and protect the health of future generations.

Reference: Diddier Prada, Beate Ritz, Ann Z. Bauer, Andrea A. Baccarelli. Evaluation of the evidence on acetaminophen use and neurodevelopmental disorders using the Navigation Guide methodology. Environmental Health, 2025; 24 (1) DOI: 10.1186/s12940-025-01208-0