Acetaminophen is the only analgesic considered safe to use throughout pregnancy, and studies indicate that 50-65% of women in North America and Europe take the drug at least once while pregnant. However, little is known about how safe the drug is during pregnancy, as few clinical trials have investigated its use in pregnant women. As acetaminophen can cross the placenta, there has been increased interest in examining how the drug may affect child health outcomes.
While some studies suggest that acetaminophen does not affect child health and development, others suggest that it may negatively affect neurodevelopment. However, few studies have investigated whether prenatal acetaminophen use affects language development, which is predictive of later IQ, reading ability, and school success.
In the current study, researchers set out to investigate how prenatal acetaminophen use affects language development. To do so, they used the Illinois Kids Development Study, which included language data from 298 infants at two years old and 254 at three years old, alongside reports from their mothers on the number of times they took acetaminophen at six time points throughout pregnancy.
Ultimately, the researchers found that taking more acetaminophen during the second and third trimesters were linked to marginally smaller vocabularies and shorter utterance length at two years old. They further found that each acetaminophen use in the third trimester of pregnancy was linked to an almost two-word reduction in vocabulary by age 2.
"This suggests that if a pregnant person took acetaminophen 13 times- or once per week- during the third trimester of that pregnancy, their child might express 26 fewer words at age 2 than other children that age," said lead author of the study, Megan Woodbury, who led the research as a graduate student at the University of Illinois at Urbana-Champaign, in a press release.
"At age three, greater acetaminophen use during the third trimester was related to parents ranking their kids as lower than their peers on their language abilities. That outcome was seen primarily in male children." said Susan Schantz, Professor Emerita at the Department of Comparative Biosciences at the University of Illinois at Urbana-Champaign, in a press release.
To explain the findings, the researchers noted that the second and third trimesters are critical times for brain development. While hearing develops in the second trimester, language development begins in the third trimester before the baby is born.
They added that the findings shouldn’t make people afraid of taking acetaminophen for fever or serious pain and discomfort during pregnancy as there aren't other options available. They noted, however, that pregnant women should 'perhaps' be more cautious about taking acetaminophen to treat minor aches and pains.
Sources: Science Daily, Nature
