A Study to Evaluate the Effectiveness of NuvaRing® to Prevent Pregnancies in Chinese Women (P06450)

13 cycles of ENG-EE (NuvaRing) vaginal ring use. Each cycle 28 days, with a 21-day active treatment period followed by 7-day ring-free period. One ring per cycle, each ring containing 11.7 mg ENG and 2.7 mg EE, and releasing on average 120 mcg/day of ENG and 15 mcg/day of EE.

13 cycles of DRSP-EE tablet use. Each cycle 28 days, with a 21-day active treatment period followed by a 7-day tablet-free period. Participants received total of 21 tablets per cycle, each tablet contained 3 mg DRSP and 30 μg EE.