A randomised double-blind trial to determine the bleeding profile of the prolonged-release contraceptive dienogest 2 mg/ethinylestradiol 0.02 mg versus an immediate-release formulation of drospirenone 3 mg/ethinylestradiol 0.02 mg.

Background: Dienogest (DNG) 2 mg/ethinylestradiol (EE) 0.02 mg is the first low-dose combined oral contraceptive (COC) with a prolonged-release formulation that allows stable plasma concentrations and has high contraceptive efficacy (Pearl index: 0.2).