ABSTRACT
The purpose of this study was to establish a new coagulation index to distinguish
severe preeclampsia from normal pregnancy using optimal coagulation parameters. The
difference between platelet counts in early gestation and before delivery (ΔPlt =
[platelet counts before delivery] - [platelet counts in early gestation]) was calculated
as an index of changes in platelet counts. Antithrombin (AT) activity, thrombin-antithrombin
(TAT) complex, fibrin degradation products (FDP) D-dimer, and ΔPlt were investigated
in 72 cases of normal pregnant women in the third trimester of pregnancy and 56 cases
of severe preeclampsia. The new coagulation index was calculated using multivariate
logistic regression analysis. As a result, in a case using four parameters, the following
formula was obtained: Y = (-0.019 × AT activity) + (0.067 × TAT) + (0.067 × D-dimer)
+ (-0.064 × ΔPlt) + 0.706. According to this formula, coagulation indices in normal
pregnant women and in patients with severe preeclampsia were -0.77 ± 0.51 and 1.41
± 1.56, respectively (p < 0.0001). Among patients with severe preeclampsia, coagulation
and fibrinolysis disorders before delivery were typical in patients terminated by
cesarean section (coagulation index = 1.62 ± 1.66) compared with those with successful
vaginal delivery (coagulation index = 0.52 ± 0.34) (p < 0.05). These facts suggest
that an excessive hypercoagulable state is associated with the termination of pregnancy
resulting from the aggravation of preeclampsia. From the viewpoint of coagulation
and fibrinolysis disorders, the predictive value in order to decide the optimal time
for the termination of pregnancy could be recommended when the coagulation index exceeded
1.20.
KEYWORD
Preeclampsia - coagulation index - platelet counts - FDP D-dimer - thrombin-antithrombin
(TAT) complex
