RESUMEN
RESEARCH QUESTION: Does a progestin-primed ovarian stimulation (PPOS) protocol with dydrogesterone from cycle day 7 yield similar outcomes compared with a gonadotrophin-releasing hormone (GnRH) antagonist protocol in the same oocyte donors? DESIGN: This retrospective longitudinal study included 128 cycles from 64 oocyte donors. All oocyte donors had the same type of gonadotrophin and daily dose in both stimulation cycles. The primary outcome was the number of cumulus-oocyte complexes (COC) retrieved. RESULTS: The number of COC retrieved (mean ± SD 19.7 ± 10.8 versus 19.2 ± 8.3; Pâ¯=â¯0.5) and the number of metaphase II oocytes (15.5 ± 8.4 versus 16.2 ± 7.0; Pâ¯=â¯0.19) were similar for the PPOS and GnRH antagonist protocols, respectively. The duration of stimulation (10.5 ± 1.5 days versus 10.8 ± 1.5 days; Pâ¯=â¯0.14) and consumption of gonadotrophins (2271.9 ± 429.7 IU versus 2321.5 ± 403.4 IU; Pâ¯=â¯0.2) were also comparable, without any cases of premature ovulation. Nevertheless, there was a significant difference in the total cost of medication per cycle: 898.3 ± 169.9 for the PPOS protocol versus 1196.4 ± 207.5 (P < 0.001) for the GnRH antagonist protocol. CONCLUSION: The number of oocytes retrieved and number of metaphase II oocytes were comparable in both stimulation protocols, with the advantage of significant cost reduction in favour of the PPOS protocol compared with the GnRH antagonist protocol. No cases of premature ovulation were observed, even when progestin was started later in the stimulation.