Obstetric complications and affective psychoses. Two case-control studies based on structured obstetric records.

BACKGROUND: Unlike schizophrenia, little interest has been taken in the incidence of obstetric complications in affective psychoses. AIMS: To find out whether obstetric complications are more common in affective psychoses than matched controls. METHOD: Two hundred and seventeen probands with an in-patient diagnosis of affective psychosis who had been born in Scotland in 1971-74, and a further 84 born in 1975-78, were closely matched with controls and the incidence of obstetric complications in the two compared using obstetric data recorded in a set format shortly after birth. RESULTS: Abnormal presentation of the foetus was the only complication significantly more common in the affective probands in the 1971-74 birth cohort and artificial rupture of the membranes was the only event more common in the probands in the 1975-78 cohort. Both are probably chance findings. CONCLUSION: It is unlikely that the incidence of obstetric complications is raised in people with affective psychoses of early onset.