Research links acetaminophen use during pregnancy to higher ADHD risk

INDIANAPOLIS (WISH) — After research released last month, many pregnant women are concerned about how to deal with pain.

Researchers linked acetaminophen use during pregnancy to ADHD in children. ADHD, a neurodevelopmental disorder, can cause inattention, hyperactivity and impulsivity. The causes are unknown but research is ongoing and genetics are believed to play a role. Acetaminophen is the active ingredient in Tylenol and hundreds of other drugs and has been thought to be safe during pregnancy.

The CDC estimates about 65 percent of pregnant women use acetaminophen. The research shows taking it for 29 days or more during pregnancy doubled the expected risk of ADHD.

Information was gathered from more than 95,000 mothers and nearly 113,000 children born between 1999 and 2009.

This isn’t the first time an association has been made with acetaminophen and ADHD either. UCLA released a study in 2014 that said taking the drug during pregnancy increased the risk of ADHD by 13 percent to 37 percent and if taken more than 20 weeks in pregnancy the risk increased 50 percent.

Riley Hospital for Children at IU Health Dr. William Kronenberger said the recurring studies prove some sort of relationship, but shouldn’t affect clinical decisions just yet.

“Now why that association occurs is the big question. It does not necessarily mean that the acetaminophen caused the ADHD. It could very well be that there’s some other factor at work here that is related to both acetaminophen used and ADHD,” Dr. Kronenberger said.

Some groups are speaking out against the research including the American College of Obstetricians and Gynecologists and the nonprofit Children and Adults with ADHD. They say the results don’t make biological sense.

Both groups and Dr. Kronenberger question the methods used during this research. The researchers used questionnaires to keep track of the women’s acetaminophen use and calculated the number of children diagnosed with ADHD by codes in their medical records. They feel the researchers should independently verify the acetaminophen use and diagnoses.

Dr. Kronenberger said the only known predictor of ADHD at this point is genetics. So if mom, dad, or other biological relatives have ADHD the child is more likely to as well. There is also research indicating drinking alcohol or smoking during pregnancy can increase the risk of ADHD.