RESUMEN
Objective: To explore the use of weekly continuous dosing of corifollitropin α in DuoStim cycles. Design: Pilot-matched case-control study. Setting: Private fertility center. Patients: Cases were defined as DuoStim cycles performed from November 2022 to May 2023 receiving weekly continuous dosing of corifollitropin α (n = 15). Controls were chosen from a database comprising DuoStim cycles conducted at our institution during the years 2021/2022. Matching was done on a 1-to-1 basis, based on antimüllerian hormone values (±0.4 pmol/L) and age (n = 15). Interventions: Injections of corifollitropin α once every 8 days, along with uninterrupted oral administration of micronized progesterone 200 mg/d (for luteinizing hormone surge prevention) throughout the follicular and luteal phases for ovarian stimulation. Oocyte retrieval. Main outcome measures: Total number of cumulus-oocyte complexes and metaphase II oocytes obtained in follicular + luteal phase stimulation. Secondary outcomes evaluated fertilization rates, number of blastocysts, days of stimulation, number of injectables required, and gonadotropin cost. Results: The study group achieved similar total oocyte and MII yield vs. daily follicle-stimulating hormone protocol (13.3 ± 6.9 vs. 11.8 ± 6.1 and 10.4 ± 6.3 vs. 9.2 ± 4.6, respectively). All secondary outcomes showed no significant differences. The study group experienced a significant reduction of injections to complete a DuoStim cycle (4.5 ± 1.4 vs. 35.2 ± 12.2; mean deviation -30.7; 95% confidence interval, -37.5- to -23.9)]. Conclusions: Corifollitropin α on a weekly basis throughout a DuoStim cycle yields an equivalent number of oocytes as standard daily follicle-stimulating hormone administration while drastically reducing the number of required injections. Trial registration number: NCT05815719. EudraCT: 2022-003177-32.