Epidural labor analgesia is a potential risk factor for increased blood loss within two hours after delivery in women with gestational hypertension: a retrospective cohort study.

Abstract

Background: Postpartum hemorrhage remains the leading cause of maternal mortality during childbirth worldwide. Given that pregnant women with gestational hypertension are particularly vulnerable to blood volume reduction, there is currently insufficient evidence to determine whether epidural labor analgesia impacts these patients within the first 2 h postpartum.

Methods: A retrospective cohort study was conducted involving 1,903 term parturients with hypertensive disorders of pregnancy admitted to Guangdong Women and Children Hospital between January 2012 and December 2021. Participants were categorized into two groups based on receipt of epidural labor analgesia: the analgesia group (n = 884) and non-analgesia group (n = 1,019). Primary outcomes included early postpartum hemorrhage (PPH) defined as ≥ 300 mL blood loss within 2 h post-delivery and associated risk factors. Statistical analyses were performed using chi-square tests for categorical variables, Mann-Whitney U tests for continuous variables, and multivariate logistic regression to evaluate independent associations between epidural analgesia and PPH.

Results: Results showed significantly higher 2-h postpartum blood loss ≥ 300 mL in epidural analgesia vs non-analgesia groups among gestational hypertension patients (54.0% vs 46.0%, P = 0.003). Multivariate analysis identified epidural analgesia as an independent risk factor for postpartum hemorrhage (adjusted OR = 1.304, 95% CI:1.013-1.680, P = 0.039). Obstetric complications including placental adhesion (OR = 2.405) and macrosomia (OR = 2.644) also correlated with hemorrhage risk (all P < 0.05). Birth canal injury demonstrated a protective association (adjusted OR = 0.63, 0.49-0.81, P < 0.001).

Conclusion: Epidural labor analgesia may elevate the risk of early postpartum hemorrhage (≤ 2 h) in parturients with gestational hypertension. Clinical practice should prioritize intensive postpartum surveillance and individualized analgesic protocols to balance analgesic efficacy and hemorrhagic risk.