The pretreatment plasma levels of prothrombin fragment F1+2 and thrombin-antithrombin III complex (TAT) were measured in 56 consecutive patients with gynecological cancer and in 33 apparently healthy volunteer nonpregnant women as control. Prothrombin fragment F1+2 concentrations were significantly elevated in the 18 patients with ovarian cancer (median, 3.2 nmol/ liter; range, 0.9-17.0 nmol/liter, P < 0.0001), in the 24 patients with cervical cancer (median, 1.7 nmol/liter; range, 0.6-15.0 nmol/ liters, P < 0.0001), and in the 14 patients with endometrial cancer (median, 1.5 nmol/liter; range, 0.6-3.0 nmol/liter, P = 0.036) when compared to controls (median, 1.0 nmol/liter; range, 0. 1 -2.1 nmol/ liter). Similarly, TAT levels were significantly higher in patients with ovarian cancer (median, 5.3 microgram /ml; range, 1.3-65.0 microgram/ml , P < 0.0001), cervical cancer (median, 3.8 microgram/ml; range, 2.1 - 11.0 microgram / ml, P < 0.0001), and endometrial cancer (median, 2.7 microgram/ml; range, 1.9-19.0 microgram /ml, P = 0.008) when compared to controls (median, 2.2 microgram/ml; range, 1.0-5.0 microgram/ml). Prothrombin fragment F1+2 levels correlated with TAT levels (r = 0.659, P < 0.0001). Among ovarian cancer patients, prothrombin fragment F1+2 and TAT concentrations correlated with FIGO stage (III-IV versus 1, P = 0.01 and P = 0.003, respectively) and CA 125 levels (P 0.02 and P < 0.0001, respectively). The present data confirmed the occurrence of hemostasis activation in patients with gynecological cancer, and in particular in those with ovarian cancer.