The objective of this study is to compare the levels of the hormones norelgestromin, norgestrel, and ethinyl estradiol in the bloodstream of healthy female volunteers administered ORTHO EVRAÂ® (a transdermal contraceptive patch) and CILESTÂ® (an oral contraceptive). The open-label treatment phase of the study consists of two 28-day cycles of one treatment, a washout period of 28 days, and crossover to two 28-day cycles of the other treatment.