Smoking during pregnancy significantly increases the risk of having a child with behavioural problems, according to research conducted by Professor Kate Pickett, at the department of health sciences at the University of York.
Boys whose mothers smoked throughout pregnancy were found to be significantly more likely to have behavioural problems, be hyperactive and have low attention spans than boys whose mothers did not. The daughters of smokers were significantly more likely to display behavioural problems than girls whose mothers did not smoke. The Guardian, November 3, 2009