For sample size calculation, we assume that the cumulative percentages of patients in the triptorelin arm achieving optimal ovarian function suppression (defined as E2 ≤2.72 pg/mL or ≤10 pmol/L) will be 30% within 2 weeks, 60% within 4 weeks and 75% within 8 weeks, and that degarelix will provide more rapid suppression (i.e., 60% within 2 weeks, 95% within 4 weeks and 100% within 8 weeks). Enrollment of 25 patients in each treatment arm will provide at least 90% power to detect a difference in time to optimal ovarian function suppression between the two groups, using a two sample log-rank test with a two-sided significance level of 0.05.