New contraceptive methods.

OBJECTIVE To provide an update on the current trend toward increasing use of emergency postcoital contraception, continuous (or "extended-use") oral contraceptives (OCs) and longer-acting contraceptive delivery systems. DATA SOURCES This review is based largely upon patient care-oriented clinical experience data, including some original work submitted to the U.S. Food and Drug Administration by the primary investigators of these novel methods, supplemented, when appropriate, with basic pharmacologic and pharmacokinetic information. METHODS OF STUDY SELECTION This review is a distillation based on an exhaustive literature search of each of the following topics: emergency postcoital contraception, continuous (extended-use) oral contraception, the weekly patch, the monthly vaginal ring and the monthly injectable. The issue of OC formulations recently begun to be marketed in this country was excluded since they have been extensively reviewed elsewhere. RESULTS Emergency postcoital contraception is highly effective, though not as effective as available proactive methods of hormonal contraception. Of the popular regimens available, all have similar efficacy; those without estrogen are associated with less nausea and vomiting. The prophylactic administration of an antiemetic 1 hour prior to the first contraceptive dose can mitigate this adverse side effect. Continuous (or "extended" use) of OCs has become increasingly popular. This can decrease or eliminate menstruation as well as several menstruation-related complaints (e.g., dysmenorrhea, menstrual migraines and premenstrual symptoms). Despite the fact that combination OC regimens offer highly reliable contraception as well as several noncontraceptive health benefits, they are limited by the issue of daily compliance. To address this limitation, several longer-acting delivery systems were recently developed. The weekly patch, monthly vaginal ring and monthly injectable have efficacy and side effect profiles similar to those of comparable OC formulations. They offer the advantages of longer action and lower and more steady steroid levels and are free of the challenges associated with daily compliance. CONCLUSION We need to continue to develop new and highly effective means of contraception that offer women ease of use and minimal side effects, hence leading to successful and effective use.