Abstract: Objective　To investigate the significance of coagulation and fibrinolysis related parameters in the third trimester for predicting the postpartum hemorrhage among low-risk pregnant women. ?Methods　A total of 2 562 singleton uncomplicated primiparous women were enrolled，and their peripheral blood was taken during 32-33 gestational weeks. The platelet（PLT）count，hemoglobin（Hb），fibrinogen（Fbg）and D-dimer（D-D）levels were determined. These women were followed up till delivery. The 48 of 2 562 women developed postpartum hemorrhage，including 16 of 48 women had severe postpartum hemorrhage. ?Results　The Fbg level in severe postpartum hemorrhage group[（4.3±1.2）g/L] was lower than that in the normal pregnant group[（4.8±0.8）g/L，P＝0.007]. When the participants were divided into 2 groups（normal pregnant group and postpartum hemorrhage group），the postpartum hemorrhage group had higher D-D level than the normal pregnant group[（1.8±1.3）g/L and（1.3±0.9）g/L，P＝0.001]. When the participants were divided into 3 groups（normal pregnant group，postpartum hemorrhage group and severe postpartum hemorrhage group），the D-D level in the severe postpartum hemorrhage group was the highest with statistical significance[（2.4±1.7）g/L and（1.5±0.8）g/L，P＝0.000]；[（2.4±1.7）g/L and（1.3±0.9）g/L，P＝0.000]. The PLT count in severe postpartum hemorrhage group was less than that in normal pregnant group[（172.4±38.9）×109 and（197.8±50.9）×109，P＝0.044）. The Fbg level determined in the third trimester had significance to predict postpartum hemorrhage among low-risk pregnant women [odd ratio（OR）＝ 1.89，95% confidence interval（CI）: 1.68-2.03]. The D-D level had the prediction significance（OR＝2.09，95%CI: 1.78-2.30）. The decreasing PLT count in the third trimester had no obvious prediction significance（OR＝1.50，95%CI:0.68-1.93）. ?Conclusions　The D-D and Fbg levels in the third trimester could predict postpartum hemorrhage.

Key words: Postpartum hemorrhage, Severe postpartum hemorrhage, Platelet, Fibrinogen, D-dimer