Pregnant woman
This is a representational image. A pregnant woman is pictured holding her stomach June 7, 2006 in Sydney, Australia. Getty Images

Mothers that took the over-the-counter drug acetaminophen when pregnant boosted speech delays in girls at 30 months old, new research suggests. Acetaminophen use during pregnancy did not have an increased effect on newborn boys, however.

In a study published Wednesday in the "European Psychiatry," researchers from the Icahn School of Medicine at Mount Sinai evaluated 754 women while eight to 13 weeks pregnant. Researchers asked female participants to document the number of acetaminophen pills consumed — like Tylenol — between their conceiving period and enrollment in the study. The amount of acetaminophen taken in by each pregnant participant was examined through a urine test.

The study's results determined that acetaminophen use during pregnancy should be limited to avoid speech development complications in newborn babies.

"Given the prevalence of prenatal acetaminophen use and the importance of language development, our findings, if replicated, suggest that pregnant women should limit their use of this analgesic during pregnancy," said Shanna Swan, PhD, professor of environmental and public health at Mount Sinai and the study's senior author, according to a EurekAlert news release. "It's important for us to look at language development because it has shown to be predictive of other neurodevelopmental problems in children."

The prevalence of speech delays, which is a communicative disorder that results in less than 50 words being spoken, was determined in the study through a nurse's evaluation and a string of follow-up questions in a survey that asked the mother of their child's language abilities after hitting 30 months of age.

The communicative hindrance was seen in 10 percent of all participants, with newborn boys being more susceptible to the disorder. Mothers that consumed higher concentrations of acetaminophen and gave birth to newborn girls, however, were more likely to experience such impediments overall compared to mothers who didn't consume the over-the-counter drug.

The maternal use of acetaminophen was previously associated with other health risks for newborns, including Attention Deficit Hyperactivity Disorder (ADHD). A study in October 2017 confirmed that long-term use of the drug among pregnant women showed a significant connection to ADHD.

Acetaminophen has also been linked to the development of autism, according to a 2016 study published in the "International Journal of Epidemiology."

Acetaminophen variants, like Tylenol, are considered to be safe for pregnant women to consume. It is frequently prescribed to pregnant women as a way to alleviate pain, according to CNN. While the Mount Sinai study isn't recommending for the usage of acetaminophen to be cut out altogether, it suggests that consumption among pregnant women should be restricted.

A representative from the study did not immediately return International Business Times request for comment.