Psychiatric morbidity is related to a chain of prenatal and perinatal adversities.

Background: Most studies on the effects of early risk factors on future mental health focus on specific obstetric complications as risk factors for specific disorders. However, obstetric complications rarely occur in isolation, and the same holds for psychiatric problems.

Aims: To study prenatal and perinatal risk factors for psychiatric multimorbidity in early adulthood and to determine whether these differ from risk factors for monomorbidity.