Maternal Mortality and Analgesia: The Unseen Connection of Epidurals and Postpartum Hemorrhage, study finds

Postpartum hemorrhage (PPH) remains the leading cause of maternal mortality globally, particularly affecting women with gestational hypertension due to their vulnerability to blood volume reduction. A recent retrospective cohort study analyzed the impact of epidural labor analgesia on blood loss within two hours post-delivery in this specific population, a critical period where up to 80% of total blood loss can occur.

Study Population and Methodology

The study included 1,903 participants who met the diagnostic criteria for gestational hypertension and were candidates for vaginal delivery. Data were meticulously collected from electronic medical records spanning nearly a decade. Comprehensive statistical analyses were performed using SPSS and R, encompassing both bivariate and multivariate logistic regression to explore associations with postpartum hemorrhage defined as blood loss of ≥300 mL. Results highlighted a prevalence of 16.9% of participants experiencing PPH of ≥300 mL. Multivariate logistic regression identified epidural analgesia as an independent risk factor for early postpartum hemorrhage (adjusted odds ratio (OR) = 1.30, 95% CI: 1.01–1.68, P = 0.039), alongside macrosomia and placental adhesion. In contrast, birth canal injury appeared protective against PPH. Notably, traditional risk factors such as age, BMI, and oxytocin use did not demonstrate significant associations with early blood loss. Prior studies have suggested that epidural analgesia does not increase PPH risk in non-hypertensive populations, raising questions about the unique pathophysiology associated with gestational hypertension. The mechanisms proposed include uteroplacental perfusion dysregulation due to vasospasm, which may impair uterine contractility, and potential disruptions to the vascular-coagulation pathway enhancing bleeding risk. Furthermore, the analysis reinforced previous findings where high BMI correlates with increased PPH risk. Critically, the definition of a ≥300 mL postpartum hemorrhage threshold was employed based on prior studies indicating its clinical relevance for early identification of PPH risk. However, the exclusive focus on the first two hours postpartum may overlook significant later blood loss, necessitating ongoing monitoring up to 24 hours.