Acetaminophen Use in Pregnancy: What the Evidence Shows

By Anna Fox, MD

Acetaminophen, commonly known by the brand name Tylenol, is one of the most frequently used pain relievers during pregnancy. For decades, it has been recommended by doctors as the safest option for treating fever and mild to moderate pain in expectant mothers. Recent research has prompted renewed public discussion about its use and potential risks.

Observational studies have explored possible links between prenatal acetaminophen exposure and childhood outcomes such as attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder, and developmental delays. Some studies have reported associations, particularly with long-term or frequent use during pregnancy. These findings have led to headlines and cautionary statements from groups of researchers urging careful use.

Association does not equal causation. The studies that suggested this linkage cannot fully account for confounding factors, such as the underlying illness and reason for acetaminophen use. Fever, infection, inflammation, and pain themselves are known risks to fetal development, making it difficult to separate the effects of the drug from the condition being treated. In this context, acetaminophen provides a net benefit when used appropriately.

The American College of Obstetricians and Gynecologists (ACOG) released a statement, “In more than two decades of research on the use of acetaminophen in pregnancy, not a single reputable study has successfully concluded that the use of acetaminophen in any trimester of pregnancy causes neurodevelopmental disorders in children. In fact, the two highest-quality studies on this subject—one of which was published in the Journal of the American Medical Association (JAMA) last year—found no significant associations between use of acetaminophen during pregnancy and children’s risk of autism, ADHD, or intellectual disability.”

The U.S. Food and Drug Administration (FDA) states that current evidence does not conclusively show that acetaminophen causes neurodevelopmental problems and continues to regard it as appropriate for use in pregnancy when clinically indicated. Doctors and midwives providing pregnancy care generally advise using the lowest effective dose for the shortest necessary duration.

The consensus among medical organizations is one of cautious reassurance. Pregnant women should consult their prenatal care provider before taking any medication, including over-the-counter drugs. Decisions should be guided by balanced evidence rather than alarm, weighing both the potential risks of medication and the known dangers of untreated illness.