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

ObjectiveTo reassess and compare cycle control attained with two combined hormonal contraceptives, norgestimate (NGM)/ethinyl estradiol (EE) 25 μg and norethindrone acetate (NETA)/EE 20 μg, by new general criteria recommendations for all combined hormonal contraceptives.DesignAnalysis of bleeding data for cycles 1–6 from a randomized, multicenter trial.Setting221 North American centers.Patient(s)Healthy, sexually active women (18–45 years old).Intervention(s)NETA/EE: 1 mg NETA/20 μg 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 μg; days 8–14: 215 μg; days 15–21: 250 μg) and 25 μg 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 μg (range 21.0%–34.4%) than with NETA/EE 20 μg (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 μg (95.2%–97.5%) than with NETA/EE 20 μg (78.5%–84.2%).Conclusion(s)The NGM/EE 25 μg has a lower incidence and comparable length of unscheduled bleeding and a higher incidence of scheduled bleeding than NETA/EE 20 μg in this post hoc analysis.