A long-term study of people's mental health by researchers at Cambridge University and the Medical Research Council has found that events very early in people's lives can have effects on their mental health years later. The forty-year study focused on anxiety and depression and found that those with poorer mental health over time were more likely to be smaller at birth and tended to reach developmental milestones later than those with good mental health. The differences with regards to early development were apparent not only for those with severe problems with their mental health but also for those with mild to moderate symptoms of depression and anxiety over time. The study supports a proposed 'fetal programming' model for depression which suggests that prenatal stress may result in permanent maladaptive changes to the developing child's brain.
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