Hormonal Contraception - Effectiveness

Effectiveness

Modern contraceptives using steroid hormones have perfect-use or method failure rates of less than 1% per year. The lowest failure rates are seen with the implants Jadelle and Implanon, at 0.05% per year. According to Contraceptive Technology, none of these methods has a failure rate greater than 0.3% per year. The SERM ormeloxifene is less effective than the steroid hormone methods; studies have found a perfect-use failure rate near 2% per year.

Long-acting methods such as the implant and the IUS are user-independent methods. For user-independent methods, the typical or actual-use failure rates are the same as the method failure rates. Methods that require regular action by the user—such as taking a pill every day—have typical failure rates higher than perfect-use failure rates. Contraceptive Technology reports a typical failure rate of 3% per year for the injection Depo-Provera, and 8% per year for most other user-dependent hormonal methods. While no large studies have been done, it is hoped that newer methods which require less frequent action (such as the patch) will result in higher user compliance and therefore lower typical failure rates.