Does Taking Tylenol in Pregnancy Increase the Risk of Autism?

This question has been widely discussed in the media and in politics. Understandably, many parents and patients want clear answers. Here is what the research currently shows.

What Earlier Studies Found

Some early studies suggested that children exposed to acetaminophen (Tylenol) in pregnancy might have a slightly higher chance of developing autism. However, these studies were observational, which means they could not fully account for other important factors such as genetics, family history, or social circumstances. These factors are essential when assessing whether a true cause-and-effect relationship exists.

What Newer Research Shows

More recent, higher-quality studies have taken a closer look by comparing siblings within the same families. These sibling-control studies help remove many of the confounding factors that can confuse results.

• A large population-based study found a small increase in autism risk at first.

• When comparing siblings, the increase disappeared. This suggests that family and genetic factors, not acetaminophen itself, likely explain the earlier findings.

What About Biomarker Studies?

Some studies measured acetaminophen levels in umbilical cord blood and found a link with autism risk. However, these results are still limited, may be affected by unmeasured factors, and have not been confirmed in sibling studies.

What Do Expert Groups Say?

Major medical organizations, including the Society for Maternal-Fetal Medicine (SMFM), American College of Obstetricians & Gynecologists (ACOG), World Health Organization (WHO), and the American Academy of Pediatrics (AAP), do not recommend changing current medical practice. At this time, the evidence does not support a causal link between acetaminophen use in pregnancy and autism. However, these bodies also acknowledge scientific uncertainty and urge continuation of further research and cautious use in clinical decision-making, which is standard in evidence-based medicine.

Bottom Line

• Current data do not show that acetaminophen causes autism.

• Apparent risks seen in earlier studies are now thought to be due to family, genetic, or social factors.

• Medical experts continue to view acetaminophen as safe for use in pregnancy when needed.

Why Uncertainty Still Matters

• Science is always evolving, and researchers continue to study this question.

• Evidence-based medicine means using the best available data today, while staying open to new findings.

• Decisions about any medication in pregnancy should be individualized, weighing benefits (such as treating fever or pain) against any potential risks.

• Talking with your healthcare provider can help tailor decisions to your specific situation.