Schizophrenia: A long-term consequence of hemolytic disease of the fetus and newborn?

In the last decade, schizophrenia has been increasingly conceptualized as a neurodevelopmental condition. Brain development is thought to be perturbed prenatally and/or neonatally through genetic and/or teratogenic mechanisms leading to neurobehavioral abnormalities in infancy [1,2] and childhood [2-4], followed by psychosis in adulthood. Genetic factors likely account for 80 percent to 85 percent of the variance in risk for schizophrenia [5]. Yet, a significant proportion of the liability for this mental disorder remains unaccounted for in this estimation. Evidence demonstrates that factors during pregnancy and delivery (e.g., obstetric complications, influenza exposure, famine, stress) [[6-12] may account for at least some of this unexplained variance. In the case of obstetric complications (OCs), 20-30 percent of schizophrenia patients have a history of one or more serious OC(s) [6], indicating that OCs could play an etiologic role in a sizable proportion of this population [13]. Furthermore, OCs appear to be associated with a more severe form of schizophrenia [13], and are associated with structural brain abnormalities such as ventricular enlargement [14,15].