Coagulation and fibrinolysis variables in pregnant women with type 1 diabetes mellitus.

Background: Many studies have reported changes in the hemostatic system in patients with type 1 diabetes in whom coagulation processes predominate over fibrinolytic activity. The aim of this study was to assess some of the hemostatic variables during pregnancy women with in type 1 diabetes.

Material/methods: The current study included 31 pregnant diabetic women and 24 healthy pregnant women. At 12, 24, and 36 weeks of gestation, we determined blood concentrations of the following: platelet count, fibrinogen, tissue plasminogen activator antigen, and plasminogen activator inhibitor-1.

Results: When we compared pregnant diabetic women in the third trimester with those in the first trimester, we observed a statistically significant decrease in the platelet count (172.0+/-9.0 vs 200.6+/-9.8 G/L, P<0.05) and a statistically significant increase in the levels of fibrinogen (3.5+/-0.2 vs 2.9+/-0.2 g/L, P<0.05), tissue plasminogen activator antigen (14.9+/-2.2 vs 4.7+/-0.6 ng/mL, P<0.001), and plasminogen activator inhibitor-1 (17.2+/-2.8 vs 4.0+/-1.0 IU/mL, P<0.001). Similar fibrinogen, tissue plasminogen activator: A, and plasminogen activator inhibitor-1 changes were observed in pregnant women (3.8+/-0.3 vs 2.9+/-0.2 g/L, P<0.05; 7.7+/-0.9 vs 5.2+/-0.3 ng/mL, P<0.05; and 17.6+/-2.1 vs 5.1+/-1.1 IU/mL, P<0.05, respectively). Tissue plasminogen activator antigen was the only variable to significantly increase during the third trimester in pregnant diabetic women with microangiopathy compared with women without microangiopathy (21.0+/-3.2 vs 8.4+/-1.7 ng/mL, P<0.01).

Conclusions: (1) In patients with type 1 diabetes without microangiopathy and with good metabolic control, fibrinogen and tissue plasminogen activator antigen concentrations and changes in the activity of plasminogen activator inhibitor-1 are similar to those found in patients with a normal pregnancy; (2) the marked decrease in platelet count in patients with type 1 diabetes during pregnancy may be an additional source of plasminogen activator inhibitor-1; and (3) during pregnancy, diabetic microangiopathy leads to a greater increase of tissue plasminogen activator antigen concentration as a marker of endothelial cell injury.