OBJECTIVE

(1) To study the changes in the haemostatic variables during normal pregnancy, and (2) to compare them with the corresponding variables in a control group of nonpregnant women.

METHODS

University Hospital.

METHODS

The study involves two groups of women: pregnant women (in 35th-40th gestational weeks (GW)) (N = 35) and a control group of nonpregnant women (N = 35).

METHODS

We examined the global tests, the variables relating to coagulation and fibrinolysis and the group of natural inhibitors of coagulation, and compared them between the two groups.

RESULTS

The pregnant women had statistically significantly higher values for: prothrombin time (PT) (P < 0.0001), thrombin time (TT) (P < 0.0001), fibrinogen (P < 0.0001), activity of factor VII (P < 0.0001), factor X (P < 0.0001) and alpha2-antiplasmin (P < 0.002), plasma concentration of D-dimer (plsDD) (P < 0.0001) and activity of heparin cofactor II (HCII) (P < 0.002). They had statistically significantly lower activity of protein C (PrC) (P < 0.0001) and of total protein S (TPrS) (P < 0.0001).

CONCLUSIONS

During normal pregnancy the activation of coagulation is counterbalanced by the activation of fibrinolysis, which maintains the haemostatic balance.