Scheduled and unscheduled bleeding patterns with two combined hormonal contraceptives: application of new recommendations for standardization

Objective: To reassess and compare cycle control attained with two combined hormonal contraceptives, norgestimate (NGM)/ethinyl estradiol (EE) 25 mu g and norethindrone acetate (NFTA)/EE 20 mu g, by new general criteria recommendations for all combined hormonal contraceptives.Design: Analysis of bleeding data for cycles 1-6 from a randomized, multicenter trial.Setting: 221 North American centers.Patient(S): Healthy, sexually active women (18-45 years old).Intervention(S): NETA/EE: 1 mg NETA/20 mu g EE, days 1-21 of each cycle and 75 mg of ferrous fumarate, days 22-28; NGM/EE: triphasic NGM in 7-day increments (days 1-7: 180 mu g; days 8-14: 215 mu g; days 15-21: 250 mu g), and 25 mu g EE, placebo on days 22-28.Main outcome Measure(s): Cycle control evaluated from patients' daily diaries.Result(S): For cycles 1-6, there was a statistically significant lower incidence of unscheduled bleeding/spotting with NGM/EE 25 mu g (range 21.0%-34.4%) than with NETA/EE 20 mu g (range 33.0%-46.6%). Of the women who had unscheduled bleeding/spotting, the mean number of days per cycle of bleeding/spotting was comparable. A statistically significant higher incidence of scheduled bleeding was seen with NGM/EE 25 mu g (95.2%-97.5%) than with NETA/EE 20 mu g (78.5%-84.2%).Conclusion(S): The NGM/EE 25 mu g has a lower incidence and comparable length of unscheduled bleeding and a higher incidence of scheduled bleeding than NETA/EE 20 mu g in this post hoc analysis. (Fertil Steril (R) 2009;92:434-40. (C) 2009 by American Society for Reproductive Medicine.)