Objective To compare the clinical outcomes of progestin-primed ovarian stimulation (PPOS) with mild stimulation protocol in patients with diminished ovarian reserve.

Methods The patients with diminished ovarian reserve received in vitro fertilization-embryo transfer were retrospectively analyzed and divided into two groups: PPOS group and clomiphene citrate mild stimulation group. Then, the rate of premature luteinizing hormone surge, dose and duration of gonadotropin, retrieved oocyte number (rate), mature oocyte number (rate), fertilization oocytes number (rate), the number of viable embryos, etc, were analyzed.

Results There were 972 patients included, with 486 patients in each group. The premature luteinizing hormone surge rate in PPOS protocol was significantly lower than that in the mild stimulation group (6.17% vs 39.92%, P < 0.001). There were no significant differences in retrieved oocytes number (rate), mature oocyte number, and some embryological characteristics between the two groups. The duration and dose of gonadotropin in the PPOS group were significantly greater than those in the mild stimulation group (P < 0.001).

Conclusions Compared with mild stimulation protocol, the PPOS protocol can effectively inhibit the premature luteinizing hormone surge in diminished ovarian reserve patients. Therefore, PPOS protocol can offer an option for diminished ovarian reserve patients who received in vitro fertilization-embryo transfer.