New research suggests that children of mothers who use acetaminophen during pregnancy are much more likely to develop hyperkinetic disorders and behavioral problems associated with attention deficit hyperactivity disorder, compared with children of mothers who do not use the pain-relieving drug during pregnancy.
This is according to a study recently published in JAMA Pediatrics.
According to the research team, including Zayan Liew of the University of California, Los Angeles, acetaminophen (paracetamol) is the most commonly used drug to treat pain and fever during pregnancy.
The Mayo Clinic state that the majority of pregnant women can safely take acetaminophen while pregnant.
But the investigators note that previous research has linked the drug to hormone disruption - a process that could impact fetal brain development.
With this in mind, the research team decided to assess whether acetaminophen use during pregnancy could increase a child's risk of behavioral problems linked to attention deficit hyperactivity disorder (ADHD) or hyperkinetic disorders (HKDs) - psychiatric syndromes that emerge during early childhood.
Risk of child behavioral problems 'increases with maternal acetaminophen use'
For the study, the investigators analyzed 64,322 children and their mothers who were a part of the Danish National Birth Cohort from 1996-2002.
Researchers found that children of mothers who used acetaminophen during pregnancy are more likely to be diagnosed with HKDs and ADHD-like behavioral disorders.
Mothers were required to report their use of acetaminophen during pregnancy and any child behavioral problems via a questionnaire.
Researchers also retrieved HKD diagnoses before 2011 from the Danish National Hospital Registry or the Danish Psychiatric Central Registry, while prescriptions for ADHD were identified from the Danish Prescription Registry.
More than 50% of mothers reported using acetaminophen at some point during pregnancy.
For these mothers, their children were more likely to be diagnosed with HKD, more likely to have ADHD-like behaviors at age 7 and were more likely to use medications for the disorder.
Furthermore, the researchers found that these risks increased further when mothers used acetaminophen in more than one trimester during pregnancy.
Findings could explain increased prevalence of behavioral disorders
According to the Centers for Disease Control and Prevention (CDC), the percentage of children diagnosed with ADHD is increasing. In 2003, 7.8% of children had the disorder, and this figure increased to 11% in 2011.
The researchers say their findings suggest that because fetal exposure to acetaminophen is frequent during pregnancy, this could explain the increasing prevalence of ADHD and other childhood behavioral disorders. But they note that further research is needed to determine this association.
In an editorial linked to the study, Miriam Cooper, of Cardiff University School of Medicine in the UK, says that although the results of this research provide preliminary evidence that prenatal exposure to acetaminophen may increase the risk of behavioral disorders in childhood, the study does not present a causal association.
"Findings from this study should be interpreted cautiously and should not change practice.
However, they underline the importance of not taking a drug's safety during pregnancy for granted, and they provide a platform from which to conduct further related analyses exploring a potential relationship between acetaminophen use and altered neurodevelopment."
Medical News Today recently reported on a review suggesting that child exposure to industrial chemicals may be causing a "silent epidemic" of brain development disorders worldwide.