Prenatal and perinatal risk factors for schizophrenia, affective psychosis, and reactive psychosis of early onset: case-control study

A few specific pregnancy and perinatal factors were associated with the subsequent development of psychotic disorder, particularly schizophrenia, in early adult life. The association of small size for gestational age and bleeding during pregnancy with increased risk of early onset schizophrenia among males could reflect placental insufficiency.