The changes in coagulation and fibrinolysis parameters during pregnancy, delivery and 3 days after delivery were evaluated in normotensive and gestational diabetes pregnant women. Normal pregnant women (n = 60) and pregnant women with gestational diabetes (n = 15) formed the study population. Coagulation and fibrinolysis parameters were estimated using commercial tests. Antithrombin III, thrombin-antithrombin III complexes, heparin cofactor II, protein C, protein S, tissue plasminogen activator, (t-PA) D-dimer and plasminogen activator inhibitor (PAI-1 and PAI-2) activities in normal and gestational diabetes pregnancies were determined. Thrombin-antithrombin III complexes increased and coagulation inhibitors decreased in gestational diabetes. Plasminogen activator inhibitors remained unchanged and t-PA levels increased in gestational diabetes.