Comparison of two triphasic oral contraceptives containing either gestodene or norethindrone: a randomized, controlled trial.Contraception. 1993 Oct; 48(4):291-301.C
Two triphasic oral contraceptives containing either gestodene or norethindrone as the progestogenic compound combined with ethinyl estradiol were compared in a randomized clinical trial to assess their contraceptive reliability, clinical tolerance and cycle control. Both preparations were effective in preventing pregnancy. The gestodene preparation proved significantly superior regarding cycle control and general tolerance.