A study of 12,500 children in Sweden, Finland and Denmark has suggested a link between mothers who are overweight when they become pregnant and an increased risk of Attention Deficity Hyperactivity Disorder (ADHD) in their children. The children were monitored from their time in the womb up to school age when their teachers were asked to answer a questionnaire about the child's behaviour. The correlation between the mothers' weight and ADHD was found in moderately overweight as well as obese women. Overweight women who gained a lot of weight during their pregnancy were more at risk of having a child with ADHD than normal weight women who gained the same amount of weight while expecting.
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