A history of obstetric complications is associated with the risk of progression from an at risk mental state to psychosis.

OBJECTIVE: Clinical criteria for diagnosing Clinical High Risk for psychosis are now available. However, an understanding of the factors modulating the risk of subsequent development of frank psychosis in "at risk" individuals remains elusive. The aim of the study was to identify associations between obstetric history and the development of psychotic disorders in individuals with an At Risk Mental State (ARMS).

METHODS: Obstetric data was obtained from the medical records of 82 individuals meeting ARMS criteria. The participants were followed up for a mean period of 42.3 (±28.3) months for transition to psychosis.

RESULTS: A history of at least one obstetric complication (OC) endorsed as definite on the Lewis and Murray Obstetric Complications Scale was found to be associated with increased risk of transition to schizophrenia (OR: 6.57, 95% CI:1.89-22.85). The number of definite OCs was found to be positively correlated with the proportion of converters (p<0.0001). The probability of conversion to schizophrenia was found to increase with a decrease of Apgar-1 and Apgar-5 scores (ORs: 0.40, 95% CI:0.22-0.74 and 0.25, 95% CI:0.10-0.63, respectively).

CONCLUSIONS: The findings emphasise the potential value of including obstetric data in algorithms estimating the likelihood of transition of an ARMS to full-blown psychosis.