LONDON — Acetaminophen, better known by the brand name Tylenol, is safe to use during pregnancy. According to a major medical review published today, Jan. 17, 2026, the drug does not harm a child’s brain development.
The findings appeared in the medical journal The Lancet Obstetrics, Gynaecology & Women’s Health. Professor Asma Khalil and a team of researchers from the University of London reviewed 43 high-quality studies involving hundreds of thousands of people. The study looked specifically at acetaminophen, which is known as paracetamol in many countries outside the United States.
Comparing Siblings
To ensure accuracy, the research team compared siblings. This approach helped the team determine if conditions like autism or attention deficit hyperactivity disorder (ADHD) were caused by the medication or were passed down through the family’s genes.
The review found no proven link between taking the drug while pregnant and autism, ADHD, or intellectual disabilities. Researchers say the findings should reassure pregnant women and help end the long-standing medical debate over the drug's safety.
Government and Safety Rules
The research challenges claims made in late 2025 by Donald Trump. At that time, the administration blamed the drug for rising autism cases and told pregnant women to avoid it. These claims followed a pledge by Health Secretary Robert F. Kennedy Jr. to investigate the cause of rising autism cases.
The new findings also challenge a study released by Harvard in August 2025. That study had suggested a possible link between developmental problems and using the drug heavily or for a long time.
The U.S. Food and Drug Administration (FDA) currently says there is no proof that acetaminophen causes conditions like autism or ADHD. However, the agency has previously warned health workers to be cautious about using the drug during pregnancy. Many experts are still concerned that patients are receiving mixed messages.
Risks of Untreated Symptoms
Medical experts and health organizations worry that confusing information might lead pregnant women to skip necessary care. According to the review, leaving high fevers or long-term pain untreated during pregnancy can result in serious health complications, including:
- Increased risk of miscarriage
- Premature birth
- Developmental problems in infants
Researchers emphasized that a mother’s health is essential for the safety of both mother and baby. The team noted that using acetaminophen as directed is still the best way to treat pain and fever during pregnancy.
