Purpose: The aim of this study was to compare effects of the transdermal contraceptive patch, a desogestrel/ethinyl estradiol (EE)-containing, monophasic combination oral contraceptive (COC) and a levonorgestrel/EE-containing, triphasic COC on hemostasis variables. Study Design: This was a randomized, open-label study of 104 young women who received six cycles of treatment. Blood was collected at baseline and on treatment; changes by Day 20/Cycle 6 in baseline hemostasis markers [prothrombin fragment 1+2 (F 1+2), plasmin-plasmin inhibitor complex (PAP) and fibrin degradation products (d-dimer)] were assessed. Results: All contraceptives induced similar increases in F 1+2 and d-dimer. Patch-induced PAP increases were less than with the monophasic and similar to the triphasic COC. Decreases in protein S and increases in sex hormone-binding globulin were greater with the patch than with either COC. Patch-induced increases in activated protein C resistance were greater than with the triphasic and similar to the monophasic COC. Conclusion: These contraceptives appeared to accelerate baseline procoagulation processes to a similar extent and to change coagulation potency variables differently. © 2008 Elsevier Inc. All rights reserved.