This multicenter, open-label, randomized, partially-balanced, incomplete block design study will consist of a pre-treatment phase (a screening period lasting up to 21 days), an open-label treatment phase (three 7-day treatment periods separated by 21-day washouts), and a post-treatment phase (a follow-up or early withdrawal visit). Total participation in the study is approximately 67 days. Approximately 52 subjects will be enrolled. The study population comprises healthy women, ages 18 to 45 years inclusive, who weigh at least 110 pounds, have a body mass index (BMI) between 16 and 29.9 kg per meter squared.