Sex hormone--binding globulin--a surrogate marker for the prothrombotic effects of combined oral contraceptives.

Abstract

The purpose of this study was to investigate the plausibility of serum sex hormone-binding globulin (SHBG) concentration as a risk marker for venous thromboembolism (VTE) during use of combined oral contraceptives (COC). Study design This was a prospective, randomized cross-over study. Thirty-five women were treated with COCs containing the same amount of ethinyl estradiol and either levonorgestrel (LNG/EE) or desogestrel (DG/EE). Serum SHBG and markers of hemostasis were determined before and after 2 months on each treatment. SHBG increased significantly with both preparations. Treatment with DG/EE caused more pronounced prothrombotic changes in hemostatic parameters than LNG/EE. With both treatment regimens, there was a significant correlation between changes in resistance to activated protein C (APCr) and changes in plasma SHBG. The correlation between SHBG and the well-established risk factor APCr might indicate the usefulness of SHBG as a risk marker for VTE during COC treatment.