Prenatal Acetaminophen Exposure Associated With Autism Spectrum Symptoms
Results of a new study from Spain suggest that prenatal acetaminophen exposure is associated with a greater number of autism spectrum symptoms in males and showed adverse effects on attention-related outcomes for both genders (International Journal of Epidemiology).
“To our knowledge, this is the first prospective study to report an independent association between the use of acetaminophen during pregnancy and autism spectrum symptomatology in exposed children,” the study authors write. “It is also the first paper to report differential gender effects of prenatal acetaminophen exposure on neurodevelopment.”
More than 2640 pregnant women (mean age, 31) were enrolled in the study. Ever/never use and frequency of acetaminophen use (never, sporadic, persistent) were evaluated via questionnaires at weeks 12 and 32 of pregnancy. Specific doses could not be attained.
Researchers also measured neuropsychological development among children using various tests, including the Bayley Scales of Infant Development (BSID) at 1 year as well as the McCarthy Scales of Children’s Abilities (MCSA), the California Preschool Social Competence Scale (CPSCS), the Childhood Autism Spectrum Test (CAST), and Conner’s Kiddie Continuous Performance Test (K-CPT) at 5 years. Researchers evaluated the development of nearly 89% of children at 1 year and nearly 80% of children at 5 years. Researchers Jordi Júlvez, PhD, from the Center for Research in Environmental Epidemiology in Barcelona, and colleagues reported that children born to mothers who used acetaminophen were approximately 30% more likely than non-exposed children to experience some attention impairments at 5 years of age. In addition, they found an increase of nearly two clinical symptoms of autism spectrum conditions among boys who were exposed to the drug prenatally.
Specifically, researchers noted that children who had been persistently exposed to acetaminophen in utero did not perform as well on tests measuring inattention, impulsivity, and visual speed processing. They observed that persistent exposure was linked to higher risks of hyperactivity/impulsivity symptoms in both sexes, higher risks of K-CPT commission errors and poorer detectability scores in girls, and higher CAST symptom scores in boys.
“This study is important because paracetamol is widely used among pregnant women,” said Dr Júlvez. “In our population-based cohort study, around 40% of the women reported ever used paracetamol, which is a similar prevalence observed in other similar countries.”
The authors stated that additional studies are needed that include more precise dosage measurements.
—Meredith Edwards White
