Trends and outcomes in massive primary postpartum haemorrhage and second-line therapy use: a retrospective study in a Hong Kong public hospital using the Hospital Authority electronic audit form

Abstract

INTRODUCTION: Massive primary postpartum haemorrhage (PPH; blood loss ≥1500 mL within 24 hours after delivery) is a major cause of maternal morbidity and mortality in Hong Kong. We compared the incidence, management strategies, and maternal outcomes of massive primary PPH across two time periods at a single obstetric unit in Hong Kong. METHODS: This retrospective cohort study included patients with massive primary PPH at our institution between 2006 and 2011 (retrospectively identified) and between 2017 and 2022 (identified using the prospectively completed Hospital Authority electronic audit form). Maternal characteristics, causes of PPH, treatment modalities, and outcomes were analysed. Regression analyses examined associations between second-line therapies and blood loss or hysterectomy. RESULTS: The incidence of massive primary PPH in our hospital increased from 0.27% to 0.44% (P<0.001). Use of second-line therapies also increased in the recent cohort (P<0.001). Furthermore, the recent cohort had a significantly lower median estimated blood loss than the earlier cohort (1700 mL [1500-2000] vs 2000 mL [1600-3000]), lower packed red blood cell transfusion requirements (2 [1-4] vs 4 [2-11] units), and a lower hysterectomy rate (2.2% vs 14.3%) [all P<0.001]. Regression analyses showed that second-line therapy was associated with greater blood loss overall; however, the excess blood loss associated with its use was substantially attenuated in the recent cohort. CONCLUSION: Despite the rising incidence of massive primary PPH in our hospital, maternal outcomes improved over time. These findings suggest that second-line and adjunctive medical therapies are used earlier and more frequently in contemporary practice.