Children whose mothers smoked during pregnancy perform more poorly on reading comprehension tests, according to a new study led by Dr. Jeffrey Gruen of Yale University.
“It’s not a little difference – it’s a big difference in accuracy and comprehension at a critical time when children are being assessed, and are getting a sense of what it means to be successful,” Gruen told Reuters Health in response to the results.
According to the study, children who had been exposed to high levels of nicotine during pregnancy scored, on average, 21 percent lower on tests specifically designed to measure how accurately a child reads out loud and how well they understand what they’re reading. A high level of nicotine was defined as a minimum of one pack of cigarettes per day.
Even when researchers removed other factors, like whether the children were read books by their parents, the results remained the same.
The study’s co-author, Jan Frijters of Brock University in Ontario, Canada, noted that “among students who share similar backgrounds and education, a child of a smoking mother will on average be ranked seven places lower in a class of 31 in reading accuracy and comprehension ability.”
The study analyzed over 5,000 children with IQ scores of 76 and higher. An IQ score lower than 70 can be the sign of a mental disability and, therefore, would have skewed the results.
According to national surveys performed by the US Center for Disease Control and Prevention, as many as one in six pregnant Americans still choose to smoke during pregnancy.
“We should not be happy with those rates,” said Dr. Thomas Paus of the University of Toronto, adding “Smoking during pregnancy is preventable.”
Source: The Montreal Gazette