Mothers who smoke are more likely to have children who behave badly. Researchers from the universities of York, Hull and Illinois studied more than 14,000 pairs of mothers and children taking part in the Millennium Cohort Study which involves children in the U.K. born between 2000 and 2001. The mothers were asked about their smoking during their pregnancy and about their three-year-old child's behaviour. The study took into account factors such as the mother's age, her level of education and socioeconomic status, family stability and problematic parenting but still found that light smokers were 44% more likely to have badly-behaved boys and heavy smokers 80% more likely. Both heavy and light smokers were also significantly more likely to have boys who were hyperactive or who had attention-deficit disorders. In girls light and heavy smoking in pregnancy were linked to bad behaviour but not hyperactivity or attention problems.
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