(HealthDay)—Babies born to women who smoked as few as 10 cigarettes are more apt to have thinking and learning problems later, a new study suggests.
Studies have long shown that babies born to smokers are likely to be premature, small and have behavior problems early on. The new research found that the negative health effects of tobacco exposure in the womb can last for years, taking a toll on teens' executive function—learned skills involving memory, reasoning, problem-solving and planning—that are important in school and life.
Up to 8 percent of U.S. women smoke during pregnancy, according to the U.S. Centers for Disease Control and Prevention. The authors said the new findings point to the need for more programs to help women of childbearing age quit smoking.
"Because tobacco is one of the most common substances used during pregnancy—and it's legal for adults to use—these results indicate the tremendous importance of bolstering efforts to ensure that women of childbearing age and pregnant women have increased access to evidence-based tobacco smoking cessation programs," said study first author Ruth Rose-Jacobs.
She is an associate professor of pediatrics at the Boston University School of Medicine.
For the study, Rose-Jacobs and her colleagues focused on a group of 131 teens who had been followed since before birth, and information on prenatal exposure was available. The researchers had the teens' high school teachers complete a form assessing the students' executive function.
After considering students' exposure to violence, lead and other substances as well as their backgrounds, the team found that only prenatal exposure to tobacco was linked with worse executive function in the teen years, particularly the ability to regulate behavior.
The researchers said exposure to as few as 10 cigarettes was enough to hurt thinking skills, though the study only found an association rather than a cause-and-effect link.
"Given that as few as 10 cigarettes can have a negative impact, it is imperative that we act on this and provide as much access and education as we can to help prevent these negative outcomes," Rose-Jacobs said in a university news release.
The study was published online June 1 in the journal Drug and Alcohol Dependence.
Explore further: In utero tobacco exposure can lead to executive function issues in adolescents
The U.S. Centers for Disease Control and Prevention provides more information on tobacco exposure during pregnancy.