Girls born to women who used acetaminophen during the first 3 months of pregnancy were more likely to experience language delay at 30 months, according to findings recently published in European Psychiatry.
“Multiple human and rodent studies report a range of adverse outcomes following prenatal analgesic exposure including hormonal and reproductive tract changes and increased risk of airway disease. Several studies report associations with behavioral, attentional and social deficits but few have examined cognitive development, Carl-Gustaf Bornehag, professor at Karlstad University in Sweden and colleagues wrote. “Because impaired language development is an early marker of impaired cognitive development, the current study examined sex-specific associations between estimated [acetaminophen] exposure in weeks 8 to 13 of pregnancy and language development at 30 months of age.”
Researchers conducted a population-based study including 754 women who were participating in the Swedish Environmental Longitudinal, Mother and Child, Asthma and Allergy study. They determined acetaminophen exposure by the number of maternally reported acetaminophen tablets taken between conception and enrollment, and by acetaminophen urinary concentration.
Among the women, 59.2% said they took acetaminophen between conception and enrollment. Bornehag and colleagues found that all urine samples contained acetaminophen, and urinary acetaminophen levels correlated with the amount taken during pregnancy (P < 0.01).
In addition, both the number of acetaminophen tablets and urinary acetaminophen concentration were linked to greater language delay — defined as use of fewer than 50 words — in girls, but not boys. The adjusted OR for language delay among girls whose mothers indicated six vs. zero acetaminophen tablets was 5.92 (95% CI, 1.1–31.94). The OR for language delay in girls whose mothers’ urinary acetaminophen concentration was in the highest quartile vs. the lowest was 10.34 (95% CI, 1.37–77.86).
“These results are consistent with studies that have examined [acetaminophen] in relation to IQ, and communication problems,” Bornehag and colleagues wrote. “No study to date has examined any neurodevelopmental outcome in relation to urinary [acetaminophen].”
According to researchers, study limitations include unmeasured confounding, exposure misclassification outcome misclassification and the limited number of patients available for the analysis.
“Given the prevalence of prenatal acetaminophen use and the predictive value of [language delay], these findings, if replicated, would suggest that pregnant women take the precautionary action of limiting their use of this common analgesic,” Bornehag and colleagues added. - by Janel Miller
The authors report no relevant financial disclosures.