• The primary efficacy variables are the total number bleeding and/or spotting days during the 84-day reference period and the number of bleeding and/or spotting episodes during the 84-day reference period.
  

• Secondary efficacy variables include the number of breakthrough bleeding and/or spotting days per 28-day interval, the number of breakthrough bleeding days per 28-day interval, time to first bleeding and/or spotting, duration of menses.
  

Norelgestromin/ethinyl estradiol is a contraceptive patch shown to be safe and effective for the prevention of pregnancy. The usual treatment regimen is three consecutive seven-day patches followed by one patch-free week. This cyclic method is followed in order to mimic the 28-day menstrual cycle. An extended contraceptive regimen (administration of active hormones for greater than 21 days) of oral contraceptives is a common practice among women wishing to delay or prevent withdrawal bleeding for reasons such as athletic participation or going on vacation. In addition to the convenience of reducing the frequency of withdrawal bleeds, elimination of the hormone-free interval reportedly reduces many menstrually-related symptoms (headaches, pelvic pain, breast tenderness, bloating, swelling) that occur at a greater frequency during the hormone-free interval than during the rest of the cycle. Headache is one of the most common adverse effects associated with hormonal contraceptive use. Studies have demonstrated that headaches were reduced in subjects using extended intervals of active hormone. However, one of the main side effects reported with extended regimens is breakthrough bleeding and/or spotting. Compared to cyclic regimens, extended oral contraceptive use may be associated with an increased incidence of breakthrough bleeding and spotting, especially during the first few months of use. This is a randomized (patients are assigned different treatments based on chance), open-label, multicenter study comparing the bleeding profile of norelgestromin/ethinyl estradiol patch continuous regimen to norelgestromin/ethinyl estradiol patch cyclic regimen. Safety evaluations include adverse event reporting, physical examinations, blood levels, and vital signs. The hypothesis of the study is that norelgestromin/ethinyl estradiol in an extended regimen of 84 days of active hormone would result in fewer days and episodes of bleeding compared to a traditional cyclic regimen of norelgestromin/ethinyl estradiol. Patients receive norelgestromin/ethinyl estradiol patches in a plastic sleeve. In the extended regimen patches will be applied weekly for 12 consecutive weeks followed by one week patch-free and then another three consecutive weeks of weekly patch applications. In the cyclic regimen patches will be applied for four consecutive cycles where each cycle consists of three weekly patch applications followed by one week patch-free. The total duration of treatment period is 112 days for each regimen.