Background: Oral progestin has recently been used to prevent premature LH surges in ovarian stimulation, and this progestin-primed ovarian stimulation (PPOS) is effective and safe in patients with different ovarian reserves. The current data are lacking regarding how to individualize the gonadotropin dose and regimen for women with polycystic ovarian syndrome (PCOS). A retrospective cohort trial was performed to evaluate the efficacy of progestin-primed milder stimulation with clomiphene citrate (CC) compared to the standard progestin-primed ovarian stimulation (PPOS) protocol for infertile women with PCOS.
Methods: A total of 220 PCOS women were collected and classified into the study group (HMG 150 IU/d + CC 50 mg/d + MPA 10 mg/d) and control group (HMG 225 IU/d + MPA 10 mg/d). Ovulation was triggered by GnRH agonist 0.1 mg and hCG 1000 IU when dominant follicles matured. Viable embryos were cryopreserved for later transfer. The primary endpoint was the ongoing pregnancy rate. Secondary outcomes included the cycle characteristics and the live birth rate.
Result(s): The study group consumed less HMG (1470.0 ± 360.1 IU vs 1943.8 ± 372.0 IU, P < 0.001) and harvested fewer oocytes than the control group (12.2 ± 7.4 vs 18.2 ± 9.7, P < 0.001). The study group showed a higher mid-follicular LH concentration (4.49 ± 2.49 mIU/ml vs 2.52 ± 2.09 mIU/ml, P < 0.05) but no endogenous LH surge. No between-group difference was found in the incidence of ovarian hyperstimulation syndrome (OHSS) (0.91% vs 0.91%, P > 0.05). The cumulative ongoing pregnancy rate and live birth rate per patient were lower but did not reach significance compared with the control group (71.8% vs 81.8 and 64.5% vs 75.5%, respectively, both P > 0.05).
Conclusion(s): The milder PPOS with CC in PCOS women led to lower oocyte yields and suboptimal pregnancy outcomes compared to the standard PPOS treatment. The two regimens both achieved a low incidence of OHSS. The results from the CC combination regimen provide a new insight for developing a more patient-friendly protocol for PCOS women.
Keywords: Clomiphene citrate; Freeze-only; In vitro fertilization; Polycystic ovarian syndrome; Progestin-primed ovarian stimulation.