Fibrinogen activity and postpartum hemorrhage risk in women with congenital fibrinogen disorders: A multicenter real-world study

Abstract

Background

Congenital fibrinogen disorders (CFDs) are associated with an increased risk of adverse pregnancy outcomes, including postpartum hemorrhage (PPH). However, the relationship between fibrinogen activity and PPH risk remains poorly defined.

Methods

We performed a multicenter retrospective cohort study of 75 women with CFDs from three tertiary centers in China between 2012 and 2025. Pregnancy outcomes and changes in fibrinogen activity during pregnancy were assessed. Deliveries with and without PPH were compared to evaluate the association between fibrinogen activity and PPH risk.

Results

Among 163 pregnancies, 107 (65.6%) resulted in live births. Detailed delivery data were available for 92 of 107 live births, with PPH occurring in 15 deliveries (16.3%). Fibrinogen activity increased significantly across pregnancy (P < 0.01), but baseline and pre-delivery levels were similar between deliveries with and without PPH (0.72 vs. 0.68 g/L, P = 0.49; 1.24 vs. 1.16 g/L, P = 0.55). Neither the absolute nor the fold change in fibrinogen activity differed significantly between groups. Pre-delivery fibrinogen activity was not associated with PPH after adjustment for maternal age, previous PPH, and induction of labor (adjusted OR per 0.1-g/L increase, 0.99; 95% CI, 0.87–1.12; P = 0.918). Prophylactic fibrinogen replacement was more common in deliveries with PPH (93.3% vs. 68.8%, P = 0.06).

Conclusions

Most pregnancies in women with CFDs resulted in live births. PPH remained an important maternal complication, but fibrinogen activity alone may be insufficient for assessing PPH risk. The role of prophylactic fibrinogen replacement therapy requires evaluation in prospective studies.