Ovulation rate and cycle characteristics in a subsequent clomiphene citrate cycle after stair-step protocol

Objective: To determine the ovulation rate after ovulation induction with clomiphene citrate (CC) in women who had previously been ovulatory after a stair-step (CC-SS) ovulation induction. Design: Retrospective cohort. Setting: University-based tertiary fertility center. Patient(s): 61 anovulatory patients <40 years of age with polycystic ovary syndrome who underwent ovulation induction with a CC-SS protocol and a subsequent CC cycle. Intervention(s): Ovulation induction with CC. Main Outcome Measure(s): Ovulation rates and cycle characteristics. Result(s): Of 61 patients who underwent a subsequent CC cycle, 15 (25%) failed to ovulate at the previously ovulatory dose. Of those 15 patients, 13 (86.7%) ovulated after an increase in dose. The total number of follicles >= 15 mm(2.8 +/- 1.2 vs. 1.6 +/- 0.7) and peak estradiol (E-2) levels (604 +/- 272 pg/mL vs. 447 +/- 218 pg/mL) were statistically significantly higher in the CC-SS cycle compared with the subsequent CC cycle, respectively. The endometrial lining was statistically significantly thinner in the CC-SS than the CC cycle (7.8 +/- 1.8 vs. 9.2 +/- 2.7, respectively). Conclusion(s): The majority of patients who ovulate after a CC-SS protocol will ovulate after taking the previously ovulatory CC dose in a subsequent cycle. Those who do not ovulate will likely ovulate with a further increase in CC dose. ((c) 2015 by American Society for Reproductive Medicine.)