Affiliations: Eye Clinic, Medical Faculty of the RWTH Aachen, Pauwelsstraße 30, 5100 Aachen, Germany | Indiana University School of Medicine, Department of Physiology and Biophysics, Indianapolis, Indiana 46202, U.S.A. | Department of Hemostaseology and Transfusion Medicine, Universität des Saarlandes, 6650 Homburg, Germany
Abstract: Conjunctival video-capillaroscopy was used to investigate the effect of oral contraceptives on the conjunctival microcirculation of 21 healthy female subjects under normal and post ischemic conditions. The study consisted of an experimental group of ten females using oral contraceptives containing 30 μg Ethinyl Estradiol, and a control group of eleven females not using oral contraceptives. Capillary red blood cell velocity was significantly lower (35%; p<0.05) in the experimental group compared to the control group both in normal and post ischemic conditions. However, contraceptives did not seem to affect conjunctival microcirculatory autoregulation. Additional measurements included hematocrit, erythrocyte aggregation, erythrocyte rigidity, plasma viscosity and spontaneous thrombocyte aggregation. Significant differences were found in hematocrit, plasma viscosity, erythrocyte aggregation and spontaneous thrombocyte aggregation (p<0.01) where values were increased in the experimental group compared to the control group. The data found in this study suggest that Ethinyl Estradiol may be a potential risk factor in microvascular pathologies.
