Low birth weight has been associated with a range of health problems in later life including mental-health problems in childhood. A study of 823 children in Detroit looked into the effects of low birth weight on children's mental health and compared 413 children from a socially-disadvantaged community to 410 children from a middle-class suburban one. In both groups children with low birth weights were more likely to have externalising (bad behaviour) and internalising (unhappiness and anxiety) problems. Low-birth-weight children from the socially-disadvantaged community were also more likely to have problems with attention which is important as attention problems at the start of schooling are linked to lower academic achievement later.
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