The research, published in the July/August issue of the journal Child Development, found that 2-year-olds regularly exposed to cigarette smoke in utero were nearly 12 times more likely to show clinical levels of behavior problems compared to toddlers who were not exposed.

“The ability to identify these disruptive behavior patterns in exposed children, even at this young age, is very striking,” said Lauren Wakschlag, associate professor of psychiatry at the UIC College of Medicine’s Institute for Juvenile Research and lead author of the study.

Researchers evaluated 93 children between their first and second birthdays. Forty-four children were exposed to cigarette smoke before birth, and among those exposed, nearly half of their mothers reported smoking more than half a pack a day.

The behaviors of exposed and non-exposed toddlers were compared to determine if early signs of disruptive behavior were evident in young children.

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