Estradiol valerate/dienogest: a novel oral contraceptive.

OBJECTIVE: To review the pharmacology, pharmacokinetics, efficacy, and safety of the new oral contraceptive estradiol valerate/dienogest.

DATA SOURCES: Searches of PubMed (1966-July 2011) and International Pharmaceutical Abstracts (1970-July 2011) were conducted using the key words estradiol valerate, dienogest, Natazia, and Qlaira. Bibliographies of retrieved articles were reviewed to identify additional references.

STUDY SELECTION AND DATA EXTRACTION: All identified studies published in English and involving efficacy and safety of estradiol valerate/dienogest as an oral contraceptive were reviewed.

DATA SYNTHESIS: Estradiol valerate/dienogest is a 4-phasic oral contraceptive approved for the prevention of pregnancy. The 4-phasic design allows for acceptable cycle control with this hormonal combination. In efficacy trials of estradiol valerate/dienogest in women aged 18-35 years, the Pearl Index ranged from 0.40 to 1.64, a range comparable to that of other combination oral contraceptives. The safety profile was also similar to that of other oral contraceptives, with headache, metrorrhagia, breast tenderness, nausea or vomiting, acne, and weight gain reported as the most common adverse effects. Menstrual bleeding patterns and cycle control with estradiol valerate/dienogest were comparable to those of a monophasic oral contraceptive containing ethinyl estradiol/levonorgestrel. Estradiol valerate/dienogest differs from other oral contraceptives in that it necessitates more stringent dosing guidelines for maximum contraceptive efficacy. New starts should be on the first day of menses only, and a back-up method of contraception is required for the first 9 days, as compared to 7 days with other oral contraceptives. Back-up contraception is usually required for any pill taken more than 12 hours later than scheduled.

CONCLUSIONS: Estradiol valerate/dienogest is an effective oral contraceptive. Because it has more stringent start times and requires a longer duration of backup contraception and stricter adherence, estradiol valerate/dienogest should be reserved for patients who are intolerant of other combination oral contraceptives.