They say it doesn’t mean that pregnant women must never, ever take the drug, but they said women may want to avoid using it frequently until more studies have been done. “(Pregnant women) shouldn’t worry at this point,” says study author Dr. Beate Ritz, professor and chair of the epidemiology department at the University of California, Los Angeles Fielding School of Public Health. The study measured how many weeks the mother reported taking any amount of acetaminophen but did not take the dosage into account. When women reported use for 20 weeks or more, their children had a 50% increased risk for receiving ADHD medication, according to the study. I would try to avoid taking painkillers as much as I can until we know more about this.” 
 
 The study, published Monday in the medical journal JAMA Pediatrics, analyzed data from more than 64,000 children enrolled in the Danish National Birth Cohort study between 1996 and 2002. Mothers in the cohort study reported on their children’s behavior, and the researchers looked at databases to determine how many prescriptions for ADHD drugs were written and how many children received a diagnosis of a severe form of ADHD called hyperkinetic disorder, or HKD. The study authors agree that their results do not show a cause-and-effect relationship. “I don’t think one study alone is enough to say nobody should use acetaminophen in pregnancy,” said Dr. Jeff Chapa of Cleveland Clinic Children’s Hospital, who was not involved in the study. A study late last year showed that women who took acetaminophen frequently during pregnancy raised the risk of behavior problems in their children by 70 percent. Ritz says more than half of all mothers in the study reported some acetaminophen use while pregnant. If you have chronic pain, maybe don’t take acetaminophen for it.” 
 
 McNeil Consumer Healthcare, which makes Tylenol, said pregnant and breastfeeding women whould consult their doctors before taking any medication. "We are aware of the recent JAMA Pediatrics study; however, there are no prospective, randomized controlled studies demonstrating a causal link between acetaminophen use during pregnancy and adverse effects on child development," the company said in a statement.
– The bad news about acetaminophen just keeps on coming: A new study finds that use of the drug during pregnancy is linked to "ADHD-like behavioral problems" in children, CNN reports. The Danish study looked at data from more than 64,000 children and found that those who had prenatal exposure to acetaminophen had a 13% higher risk of exhibiting ADHD-like behaviors, a 29% higher risk of being prescribed ADHD medication, and a 37% higher risk of receiving a diagnosis of hyperkinetic disorder, a severe form of ADHD, USA Today reports. The risk increased the later in pregnancy the drug was taken and the longer it was taken. Women who used acetaminophen for 20 weeks or longer had a 50% higher chance of their children being prescribed ADHD medication. But the authors did not find a cause-and-effect relationship, and they note that "exhibiting ADHD-like behaviors" is not the same as actually having ADHD. Right now, doctors consider acetaminophen the "safest" pain reliever for pregnant women, NBC News reports; the study author says pregnant women "shouldn't worry at this point." What could account for the link? The authors think acetaminophen may interfere with key maternal hormones that impact fetal brain development. Another recent study also found that frequent acetaminophen use during pregnancy was linked with a 70% higher risk of behavioral problems in children.