Research published in the JAMA Pediatrics in August 2016 found an increased risk in behavioral and emotional problems in children whose mothers took the painkiller acetaminophen during pregnancy. According to the American Academy of Family Physicians, at least 2/3 of pregnant women take acetaminophen because it is considered the safest pain and fever reducer during pregnancy.
The study at the University of Bristol in England followed over 7800 women and their children for a seven-plus year period. Researchers discovered children whose mothers took acetaminophen (aka Tylenol) during pregnancy may have an increased risk of behavioral problems like attention-deficit/hyperactivity disorder (ADHD) and emotional problems, however, the study failed to prove cause and effect.
In the study group examined, researchers found behavioral problems were 20-45% more common in children whose mothers used acetaminophen while pregnant. Researchers found a 42% increased risk of behavioral problems and a 31% increased risk of hyperactivity when acetaminophen was taken between 18 and 32 weeks of pregnancy. When acetaminophen was taken at 32 weeks of pregnancy, researchers noted a 29% increased risk of emotional problems and a 46% increased risk of behavioral problems. Overall, only 5% of the children in the study demonstrated behavioral problems by 7 years of age.
Researchers theorized acetaminophen use may change a pregnant woman’s hormone levels thus affecting fetal brain development, or that acetaminophen may penetrate the placenta and affect the unborn fetus directly.
Two earlier studies produced similar findings but researchers and doctors caution pregnant women not to be alarmed because the study failed to ask two important questions, namely how often and at what doses the women in the study took acetaminophen during their pregnancies. More importantly, the study failed to prove a cause-and-effect relationship between acetaminophen use during pregnancy and behavioral problems in children. Researchers concluded more studies must be done to determine whether there is a cause-and-effect relationship between acetaminophen use during pregnancy and behavioral problems in children.
After the study was published, American College of Obstetricians and Gynecologists CEO Dr. Hal Lawrence tried to reassure pregnant women that acetaminophen use during pregnancy is safe: “This new study, and other studies that have been conducted in the past, show no clear evidence that proves a direct relationship between the prudent use of acetaminophen during any trimester and developmental issues in children.”
Dr. Tim Overton, the spokesman for the Royal College of Obstetricians and Gynaecologists, added, “Women should not be alarmed by the results of this study and we recommend that pregnant women continue to follow current guidance and take the lowest effective dose for the shortest possible time when necessary.” The best advice for pregnant women is to discuss acetaminophen use with their doctor and weigh the risks and benefits before taking any medication.