• Contraceptive efficacy is assessed with the Pearl Index and life table analysis (gross cumulative probability of pregnancy). Safety is evaluated throughout the study.
  

• Cycle control and compliance are assessed with diary cards containing bleeding information and dosing information.
  

This is an open-label, multicenter, global study to evaluate the contraceptive efficacy, cycle control, safety, compliance and subject satisfaction of the transdermal contraceptive system. Sixteen hundred healthy women will wear the contraceptive patch for either 6 or 13 cycles. The first 530 subjects will wear the patch for 13 cycles, and all subsequent subjects will wear the patch for 6 cycles. At admission Visit 1, study drug (plus 3 reserve patches) and diary cards are dispensed for Cycle 1; first patch application will be on the first day of menses. Study drug and diary cards are dispensed on day 28 of Cycle 1 (Visit 2) for Cycles 2 and 3, on day 28 of Cycle 3 (Visit 3) for Cycles 4 to 6, on day 28 of Cycle 6 (Visit 4) for Cycles 7 to 9, and on day 28 of Cycle 9 (Visit 5) for Cycles10 to13. At each of these visits, diary cards and empty medication packages are collected. Final study visits are on day 28 of Cycles 6 and 13. Diary card information is used to record compliance and bleeding information (to assess cycle control). Contraceptive efficacy is assessed by means of the Pearl Index and life table analysis (gross cumulative probability of pregnancy). Safety evaluations are based on adverse events, which are collected throughout the study, and changes in gynecologic examinations, vital signs, and laboratory results from admission to final visit.

Each transdermal contraceptive patch, containing 6 mg NGM and 0.75 mg EE, and delivering 250 ug 17-dNGM and 25 ug EE over 24 hours for 7 days, is worn for 1 week and replaced for 3 consecutive weeks. The fourth week is patch-free. The patch can be worn on: upper arm or torso, buttock, or abdomen.