Reduced hemostatic effects with drospirenone-based oral contraceptives containing estetrol vs. ethinyl estradiol.

OBJECTIVE: The effects of estetrol (E4), a natural fetal estrogen, combined with drospirenone (DRSP) were evaluated on plasma levels of sex hormone-binding globulin (SHBG), angiotensinogen and 12 hemostasis markers.

STUDY DESIGN: Combinations of 3 mg DRSP with 5 or 10 mg E4 were compared with YAZ® (20 mcg ethinyl estradiol and 3 mg DRSP; EE/DRSP) in parallel groups of 15-18 healthy young women. Main outcome was the relative change from pretreatment to the end (day 24±1) of the third treatment cycle.

RESULTS: All E4 combinations showed low estrogen impact compared to EE/DRSP. Effects on SHBG and angiotensinogen of 10 mg E4 combined with DRSP were 15%-20% that of EE/DRSP. Both E4/DRSP combinations reduced D-dimer level and the 5 mg E4/DRSP combination also decreased fragment 1+2.

CONCLUSIONS: The reduction in coagulation markers suggests an anticoagulant effect from DRSP. The indications of a low thrombosis risk for E4 preparations should be validated in larger studies. IMPLICATION STATEMENT.