Improved monofollicular ovulation in anovulatory or oligo-ovulatory women after a low-dose step-up protocol with weekly increments of 25 international units of follicle-stimulating hormone

ObjectiveTo compare the effectiveness and efficiency of two low-dose step-up protocols for ovulation induction in women with anovulatory infertility (World Health Organization group II).DesignOpen-label, prospective, randomized, group-comparative, multicenter study.SettingEighteen infertility centers in Europe and Canada.Patient(s)One hundred fifty-eight anovulatory or oligo-ovulatory infertile women.Intervention(s)Patients were randomly assigned to one of two protocols for one cycle of follitropin beta (rFSH) using a pen device. The starting dosage was 50 IU/day for 7 days. In the absence of follicles ≥12 mm, the daily dosage was increased by either 25 or 50 IU per week.Main Outcome Measure(s)The percentage of all subjects treated who ovulated after one treatment cycle (efficacy) and the total rFSH dose to reach ovulation (efficiency).Result(s)The 25-IU group had a higher incidence of monofollicular growth (41.3% of 80 vs. 21.8% of 78 women) and ovulation (81.3% vs. 60.3%), a lower cumulative rFSH dose (887 IU vs. 984 IU), and fewer cancellations due to hyperresponse (>3 follicles ≥15 mm; 5.0% vs. 20.5%). Both protocols were well tolerated.Conclusion(s)Weekly increments of 25 IU in the daily dose were more effective and efficient than 50-IU increments.