Women at the lower end of the socioeconomic distribution have higher rates of depression in pregnancy and lower rates of treatment. In this study, we investigate relationships between income and the use of psychotropic mediciness in pregnancy. This retrospective cohort study using population-based administrative datasets included all women who delivered a live infant in the province of British Columbia, Canada (population of 4.6 million), between April 1, 2000, and December 31, 2009. We compared the socioeconomic distribution in use of psychotropic mediciness in pregnancy. We included 305,984 deliveries among 217,721 women. Women at the low end of the income distribution were significantly more likely to have a diagnosis for all mental health conditions, except anxiety, which was more common in women of highest socioeconomic status. The adjusted odds ratios for psychotropic medicine use indicate that women in the lowest income quintile have lower odds of filling a prescription for a psychotropic medicine after controlling for covariates and diagnoses of mental health conditions. However, they were more likely to fill a prescription for an antipsychotic and were more likely to fill psychotropic medicines from three or more different drug categories during pregnancy. Our findings suggest that women of lower socioeconomic status are less likely to fill a prescription for a psychotropic medicine in pregnancy, a finding largely driven by their decreased likelihood of filling an antidepressant. This is despite overall higher rates of mental illness among women of lower socioeconomic status, suggesting a gap in treatment by socioeconomic status.
Keywords: Administrative data; Maternal mental illness; Psychotropic medicine use in pregnancy; Socioeconomic status.