The impact of antenatal factor XIII levels on postpartum haemorrhage: a prospective observational study

Postpartum haemorrhage (PPH) is a leading cause of maternal mortality and morbidity. Our aim was to investigate the relationships between antenatal factor XIII (FXIII), fibrinogen levels, and blood loss at childbirth.

This prospective observational study evaluated an unselected cohort of pregnant women admitted for intended vaginal deliveries of singletons at term. To determine clotting factor levels, we obtained blood samples at a maximum of three days prior to vaginal delivery. A calibrated collecting drape was used to quantify blood loss in the third stage of labour. Moderate and severe PPH were diagnosed as blood losses ≥ 500 mL and ≥ 1000 mL, respectively. In a multiple logistic regression analysis, we determined whether coagulation factors and their interactions could independently predict (severe) PPH.

We analysed 548 vaginal deliveries that occurred during the study period. Of those, 78 (14.2%) lost ≥ 500 mL and 18 (3.3%) lost ≥ 1000 mL of blood. The mean pre-delivery FXIII activity in women with PPH (79.33% ± 15.5) was significantly (p < 0.001) lower than in women without PPH (86.45% ± 14.6). A receiver operating characteristic curve analysis detected antenatal FXIII cutoff levels of 83.5% and 75.5% for PPH and severe PPH, respectively. The multiple logistic regression analysis showed that FXIII alone (p < 0.001) and its interaction with fibrinogen (p = 0.03) significantly predicted PPH. FXIII was not significantly correlated with blood loss among patients with severe PPH.

Our results suggested that antenatal FXIII levels may have a significant influence on PPH. The interaction between FXIII and fibrinogen might also provide slight advantages in forecasting PPH.