A kilo more at birth would protect against depression, obsessive compulsive disorder, attention and hyperactivity disorder and autism.
Birth weight would have consequences for the child's health and its development: a Swedish research, published in the Journal of the American Medical Association (JAMA), shows that a low weight increases the risk of psychiatric disorders.
A study done on twins
The researchers compiled the data of more than one million twins, born between 1973 and 1998 and followed them until 2013. The first findings indicated that one kilo more at birth would protect against 9 disorders including depression. , bipolarity and post-traumatic stress. A second analysis was done by looking at the characteristics shared by the twins: the environment in which they grew up, the genes, etc.
The refined results confirm that one kilo more (compared to the average weight of the participating babies - the researchers do not specify what is this average weight) reduces the risks of developing 4 psychiatric problems and diseases: depression, obsessive-compulsive disorders, attention and hyperactivity disorders and autism. An additional kilogram decreases the predispositions but also the specific risks of neurodevelopmental disorders. These decreases are small, in the case of depression, it is 5%, but for researchers, even low, these rates remain significant.
Links between fetal weight and brain growth
The origin of these differences in risk is not yet clear, but for scientists, it could be related to the brain. Reduced fetal growth in the mother's womb could disrupt brain development and increase the risk of psychiatric disorders. During pregnancy, the mother's diet has a significant impact on the child's health. For example, consuming too much fat and too much sugar can increase the risk of hyperactivity.