Association between prenatal exposure to analgesics and risk of schizophrenia

Using data from the Copenhagen Perinatal Cohort and from the Danish Psychiatric Central Register, the authors studied the relationship between prenatal exposure to analgesics and the risk of schizophrenia. The effect of prenatal exposure was adjusted for parental history of schizophrenia, second-trimester viral infections, concomitant drug treatment during pregnancy, an index of pregnancy complications, parental social status and parental age. In a risk set of 7999 individuals, 116 cases of schizophrenia were found (1.5%). Prenatal exposure to analgesics in the second trimester was associated with an elevated risk (adjusted odds ratio 4.75, 95% CI1.9-12.0).Independent of the covariates, the effect remained statistically significant. CONCLUSIONS: Independent of a wide range of possible confounders, a significant association between second-trimester exposure to analgesics and increased risk of schizophrenia was observed.