Postpartum hemorrhage following vaginal delivery: risk factors and maternal outcomes.

Abstract

BackgroundLimited understanding exists of risk factors for PPH post-vaginal delivery.ObjectiveTo identify risk factors for PPH post-vaginal delivery within a contemporary obstetric cohort.Study DesignRetrospective case-control study. PPH was classified by an estimated blood loss ≥ 500 mL. Risk factors for PPH were identified using univariable and multivariable logistic regression. We secondarily investigated maternal outcomes and medical and surgical interventions for PPH management.ResultsThe study cohort comprised 159 cases and 318 controls. Compared to a second stage duration <2 hours, a second stage ≥ 3 hours was associated with PPH (Adjusted Odds Ratio=2.3; 95% CI=1.2 – 4.6). No other clinical or obstetric variables were identified as independent risk factors for PPH. Among cases, 4% received red blood cells and 1% required intensive care admission.ConclusionAlthough PPH-related morbidity may be uncommon after vaginal delivery, PPH should be anticipated for women after a second stage ≥3 hours.