Quantitative assessment of active bleeding on contrast-enhanced computed tomography in primary postpartum hemorrhage

PURPOSE: This study aimed to evaluate whether computed tomography (CT)-derived extravasation rate from dynamic contrast-enhanced CT is associated with invasive hemostatic intervention and clinical severity in primary postpartum hemorrhage. METHODS: This retrospective single-center study included 36 patients with active intrauterine arterial bleeding on contrast-enhanced CT among 135 patients who underwent CT for primary postpartum hemorrhage between January 2020 and December 2025. The extravasation rate was calculated as the increase in extravasation volume from arterial to delayed phase divided by the interphase interval. Associations with hysterectomy and transcatheter arterial embolization (TAE), and correlations with clinical variables, were assessed. RESULTS: = 0.040), whereas the correlations with systolic and diastolic blood pressure did not reach statistical significance. CONCLUSION: CT-derived extravasation rate showed exploratory associations with hemorrhagic severity and invasive hemostatic intervention. These preliminary findings require validation in larger studies using standardized CT acquisition and measurement protocols. CLINICAL SIGNIFICANCE: Quantitative assessment of contrast extravasation on dynamic CT provides a continuous imaging measure beyond the binary presence or absence of active bleeding.