Progestin-primed ovarian stimulation protocol with or without clomiphene citrate for poor ovarian responders: a retrospective cohort study

Objective:To explore the efficacy of progestin-primed ovarian stimulation (PPOS) combined with clomiphene citrate (CC) versus PPOS protocol used alone on cycle characteristics and pregnancy outcomes for women with the poor ovarian response (POR). Methods:We performed a retrospective cohort study and a total of 578 POR patients who underwent IVF/ICSI cycles were collected and divided into Group A (HMG 300 IU/d + MPA 10 mg/d) and Group B (HMG 300 IU/d + MPA 10 mg/d + CC 50 mg/d). The primary outcome measure was the number of oocytes retrieved, other outcome measures were cycle characteristics and clinical pregnancy rate. Results:The baseline information between the two groups were not statistically significant (P > 0.05). Compared with Group A, Group B had a lower total dose of human menopausal gonadotrophin (HMG) (2998.63 +/- 1051.09 vs. 3399.18 +/- 820.75, P < 0.001) and the duration of stimulation (10.21 +/- 3.56 vs. 11.27 +/- 2.56, P < 0.001). Serum luteinizing hormone level was higher in Group B on human chorionic gonadotrophin injection day (P < 0.001). The number of oocyte for retrieval, maturation, and fertilization were significantly lower in Group B than that in Group A (P < 0.001). However, the oocyte retrieval rate, maturation rate, fertilization rate, and viable embryo rate showed no statistical difference in the two groups (P > 0.05). After adjusting for confounders, the clinical pregnancy rate (OR 1.286; 95% CI 0.671-2.470) and live birth rate (OR 1.390; 95% CI 0.478-3.990) were comparable between the two groups. Conclusions:PPOS protocol combined with CC reduces the total dose of HMG and the duration of stimulation, and can also achieve similar oocyte yields and clinical pregnancy rate compared with the PPOS protocol used alone in poor ovarian responders.