Balance of coagulation activity with fibrinolysis during use of oral contraceptives in women with insulin-dependent diabetes mellitus.

In healthy nondiabetic women, oral contraceptives (OCs) affect hemostatic function. In diabetic women, there is concern that they may also increase the risk of diabetic vascular complications. This study was designed to examine the balance between coagulation activity and fibrinolytic activity--an indirect measure of endothelial cell function--in women with insulin-dependent diabetes mellitus (IDDM) during long-term use of OCs. The study group included 11 young women with uncomplicated IDDM who were prescribed ethinyl estradiol 30 micrograms and gestodene 75 micrograms. Twelve other diabetic women not taking OCs constituted the control group. Hemostatic function was evaluated at entry and after 1,3,6, and 12 months. In women taking OCs, plasma levels of factor VII(c) increased, while fibrinogen levels did not change. Inhibition of coagulation was affected by increased levels of protein C, although plasma levels of antithrombin III and protein S remained stable. The antigen concentrations of tissue-type plasminogen activator and plasminogen activator levels themselves were unchanged. There was a proportionate increase in the concentrations of thrombin-antithrombin III complexes and D-dimer. None of the hemostatic variables changed significantly in the control group. We conclude that the balance between coagulation activity and fibrnolysis does not change during use of this OC. Our findings suggest that low-dose OCs induce a procoagulatory state that is compensated for by enhanced fibrinolytic activity.