The association between postpartum hemorrhage and postpartum depression: A Swedish national register-based study

Background Postpartum hemorrhage is an important cause of maternal death and morbidity. However, it is unclear whether women who experience postpartum hemorrhage are at an increased risk of postpartum depression. Objectives To examine whether postpartum hemorrhage is associated with postpartum depression. Methods We conducted a national register-based cohort study of 486,476 Swedish-born women who had a singleton livebirth between 2007 and 2014. We excluded women with pre-existing depression or who filled a prescription for an antidepressant before childbirth. We classified postpartum depression up to 12 months after giving birth by the presence of an International Classification of Diseases, version 10 (ICD-10) diagnosis code for depression or a filled outpatient prescription for an antidepressant. We used Cox proportional hazard models, adjusting for maternal sociodemographic and obstetric factors. Results Postpartum depression was identified in 2.0% (630/31,663) of women with postpartum hemorrhage and 1.9% (8601/455,059) of women without postpartum hemorrhage. In our unadjusted analysis, postpartum hemorrhage was not associated with postpartum depression (unadjusted hazard ratio (HR) = 1.06, 95% confidence interval (CI) 0.97-1.15). After adjusting for maternal age, parity, education, cohabitation status, maternal smoking status, and early pregnancy maternal BMI, gestational age, and birthweight, the association did not appreciably change, with confidence intervals overlapping the null (adjusted HR = 1.08, 95% CI 0.99, 1.17). Conclusions Within a population-based cohort of singleton women in Sweden with no prior history of depression, postpartum hemorrhage was not associated with postpartum depression.