CauseBack
- chromosomal abnormality (the X chromosome has a weak spot or an extra chromosome is present in pair 21)
- problems in the adhesion of genes
- metabolic disturbances due to genetic disorder
- bacterial infection (e.g. rubella), incorrect medication, drugs, malnutrition, smoking, excessive drinking, substance abuse and radiation attack during conception can all lead to the birth of a mentally handicapped baby
- premature birth, difficult labour and low weight can hinder the development of the baby's brain or do damage to it, thus causing mental handicap
- bacterial infection (e.g. meningitis), malnutrition and brain injury during infancy and early childhood can cause mental handicap
- postnatal environment the child is subjected to, such as the kind of parental care, the things it gets in touch with and the learning opportunities it is given, also has a bearing on its intellectual development