Risk Factors for Severe Secondary Postpartum Hemorrhages: A Historical Cohort Study

Background The predictive factors of secondary postpartum hemorrhage (PPH) are little known. Our principal objective was to determine if immediate PPH is a risk factor for severe secondary PPH. We also sought to identify other factors associated with severe secondary PPH. Methods Our historical cohort study included all women who gave birth (≥ 22 weeks) in our level III hospital from 2004 through 2013. The hospital discharge database enabled us to identify all women readmitted during the 42-day postpartum period or who underwent a surgical, medical, or interventional radiology procedure during their immediate postpartum hospitalization. We then examined all medical records to identify the cases involving severe secondary PPH. We studied the known risk factors of secondary PPH and assessed other potential ones: maternal age, multiple pregnancy, induction of labor, cesarean birth, preterm birth, and stillbirth. Results The study included 63 women with a severe secondary PPH and 25,696 women without a secondary PPH. Immediate PPH (aOR 2.7 [95% CI 1.3–5.6]) and maternal age ≥ 35 years (aOR 2.0 [95% CI 1.1–3.7]) were the only factors associated with severe secondary PPH. Discussion This cohort study confirms that immediate PPH is a risk factor for severe secondary PPH and reports for the first time an association between secondary PPH and advanced maternal age. It is likely that risk factors for immediate PPH are also risk factors for severe secondary PPH and thus that immediate PPH may be an intermediate factor between its own known risk factors and secondary PPH.