Effectiveness of the flexible progestin primed ovarian stimulation protocol compared to the flexible GnRH antagonist protocol in women with decreased ovarian reserve.

The aim of this retrospective cohort study was to compare the effectiveness of the new flexible progestin primed ovarian stimulation (fPPOS) protocol with the flexible gonadotropin-releasing-hormone antagonist (GnRH-ant) protocol in women with decreased ovarian reserve (DOR). Twenty-seven women who underwent fPPOS and 54 age-matched women who received GnRH-ant for pituitary suppression were included in the study. All women had DOR and underwent oocyte cryopreservation. Three-hundred IU/day FSH was started on cycle day 2-3 and 0.25 mg/day GnRH-ant or 10 mg/day medroxyprogesterone acetate was started when the leading follicle reached 14 mm or serum oestradiol level was ≥200 ng/mL. The median duration of stimulation, day of commencing pituitary suppression and duration of suppression were similar in both groups, with 8, 5, and 5 days, respectively. The median number of cumulus-oophorous complexes (4.0 vs 5.5), metaphase-two oocytes (3 vs 4), the total number of oocytes cryopreserved (3.0 vs 4.5), and oocyte maturation rates (0.67 vs 0.70) were similar between the fPPOS and GnRH-ant groups, respectively. There was one case of premature ovulation in the fPPOS group and none in the GnRH-ant group (p = 0.91). In conclusion, fPPOS may be used in women with DOR without compromising the number of oocytes retrieved and seems a viable alternative to the flexible GnRH-ant protocol.