Labour and delivery complications at birth and later mania. An Irish case register study.

BACKGROUND: Several reports postulate that manic depression and schizophrenia share environmental risk factors. Although obstetric adversity has been suggested as a risk factor for schizophrenia, few studies have examined its relationship to bipolar affective disorder. AIMS: To assess the rate of obstetric complications incurred by patients with mania compared with controls. METHOD: From the Dublin Psychiatric Case Register we identified individuals with a discharge diagnosis of mania and traced their birth records. Each case was matched with a control of the same gender, born in the same hospital, in the same year, matched for maternal age, parity and social class. Two obstetric complications scales were used to make blind evaluations of labour and delivery data. RESULTS: Patients with mania did not experience a greater frequency or severity of labour and delivery complications than their matched controls. Rates of obstetric adversity were unrelated to the presence or absence of family history of psychiatric disorder. Obstetric adversity was unrelated to the age at first diagnosis. CONCLUSIONS: These findings suggest that obstetric adversity is not a risk factor for later mania.