Hemostatic effects of a novel estradiol-based oral contraceptive: an open-label, randomized, crossover study of estradiol valerate/dienogest versus ethinylestradiol/levonorgestrel.

BACKGROUND: A novel estradiol-based combined oral contraceptive (COC) is currently available in many countries worldwide, including Europe and the US. Based on previous studies, it is expected that this estradiol-based COC will have a reduced hepatic effect compared with COCs containing ethinylestradiol with regard to proteins controlling the hemostatic balance.

OBJECTIVE: The aim of this study was to compare the hemostatic effects of the estradiol valerate/dienogest COC with a monophasic low-estrogen dose COC containing ethinylestradiol/levonorgestrel.

STUDY DESIGN: Healthy women aged 18-50 years were randomized to receive a COC containing estradiol valerate/dienogest (2 days estradiol valerate 3 mg, 5 days estradiol valerate 2 mg/dienogest 2 mg, 17 days estradiol valerate 2 mg/dienogest 3 mg, 2 days estradiol valerate 1 mg, 2 days placebo) or ethinylestradiol 0.03 mg/levonorgestrel 0.15 mg in a crossover study design. Women received each treatment for three cycles, with two washout cycles between treatments. The primary efficacy variables were the intra-individual absolute changes in prothrombin fragment 1 + 2 and D-dimer from baseline to cycle three.

RESULTS: Data from 29 women were assessed. Intra-individual absolute changes in prothrombin fragment 1 + 2 and D-dimer from baseline to cycle three were less pronounced with estradiol valerate/dienogest than with ethinylestradiol/levonorgestrel.

CONCLUSION: The novel COC containing estradiol valerate/dienogest had similar or less pronounced effects on hemostatic parameters than ethinylestradiol/levonorgestrel.