Johannes Bitzer, Maria Jesusa Banal-Silao, Hans-Joachim Ahrendt, Jaime Restrepo, Marion Hardtke, Ulrike Wissinger-Graefenhahn, Dietmar Trummer

To assess whether the combined oral contraceptive (COC) ethinylestradiol (EE) 20 μg/drospirenone 3 mg taken in a 24/4-day regimen (ie, 4-day hormone-free interval) is more effective than an EE 20 μg/desogestrel (DSG) 150 μg COC taken in a 21/7-day regimen (ie, 7-day hormone-free interval) in reducing hormone withdrawal-associated symptoms (HWAS). This double-blind, randomized study (NLM identifier: NCT01076582) was conducted at 34 centers in 12 countries. Otherwise healthy women who experienced ≥2 HWAS of headache, pelvic pain, and/or bloating when using their current COCs in a 21/7-day regimen were recruited. Subjects rated the severity of their HWAS daily on a seven-point Likert scale during a baseline cycle and during four 28-day cycles with EE/drospirenone 24/4 (n=290) or EE/DSG 21/7 (n=304). The primary variable was the mean change from baseline to cycle 4 in the composite HWAS score (sum of scores for all three symptoms) during cycle days 22-28. In the EE/drospirenone 24/4 group, the mean (standard deviation) composite HWAS score during cycle days 22-28 was reduced from 42.2 (24.8) at baseline to 12.8 (13.4) at cycle 4 (change from baseline: -30.3 [22.9]). In the EE/DSG 21/7 group, the corresponding value was reduced from 41.9 (25.8) to 14.3 (13.2) (change from baseline: -27.7 [24.8]), not significantly different versus EE/drospirenone 24/4. Bleeding pattern, treatment response, rescue medication use, compliance, quality of life, and tolerability were similar between treatments. Both EE/drospirenone 24/4 and EE/DSG 21/7 reduced the composite HWAS score from baseline to cycle 4 in otherwise healthy women. The differences between treatments were too small to be statistically significant.