New hormonal contraceptives: a comprehensive review of the literature.

Over 16 million women in the United States take oral hormonal contraceptives, yet approximately 5% experience an unintended pregnancy during the first year of use. Compliance with the regimen is important in maintaining cycle control and preventing pregnancy. New hormonal contraceptive agents, norelgestromin-ethinyl estradiol patch, etonogestrel-ethinyl estradiol vaginal ring, and medroxyprogesterone-estradiol cypionate injection, were designed to increase compliance and decrease adverse effects while maintaining efficacy.