A new study suggests a link between attention deficit hyperactivity disorder and pregnant women who take acetaminophen.

According to the study in the Journal of American Medical Assocition of Pediatrics, pregnant women who took the common pain reliever for 20 weeks or more had a 50 percent increased risk of their children eventually needing ADHD medication.

Researchers say acetaminophen may be interfering with maternal hormones that are critical for fetal brain development.

Long Island OBGYN Dr. Jill Rabin told News 12 that researchers did not find acetaminophen causes ADHD. Plus, she says the study has other limitations.

"The parents' genetic background wasn't examined...They didn't look at other medical conditions with the mom and they didn't look at psychiatric conditions including whether or not she had ADHD," said Rabin.

Many experts, including Dr. Rabin, say more research needs to be done. Expectant mothers with questions about the study should ask their doctors.