Highly purified-hMG versus rFSH in ovarian hyperstimulation in women undergoing elective fertility preservation: a retrospective cohort study

Objective: To compare recombinant FSH (rFSH) with highly purified-human menopausal gonadotrophin (hp-hMG) on ovarian response in women undergoing elective fertility preservation (FP). Methods: This retrospective study included 456 women who underwent elective FP with gonadotropin-releasing hormone (GnRH) antagonist or progestin-primed ovarian stimulation (PPOS) protocols between 01/2017-12/2021. Only the first treatment cycle of each woman was included. 341 women were stimulated with rFSH and 115 with hp-hMG, and the ovarian stimulation outcomes were compared. A multivariate linear regression assessed the impact of age, basal FSH, antral follicle count (AFC) and protocol and gonadotropin types on the outcomes. Results: Women in the rFSH group were significantly younger, and their AFC was significantly higher than those in the hp-hMG group (35.50±2.12 vs. 35.99±2.13years, p=0.034 and 13.76±6.08 vs. 11.84±6.06, p=0.002). There were no significant group differences in the amount (p=0.645) and duration (p=0.265) of FSH stimulation. The estradiol level was significantly lower for the rFSH group compared to the hp-hMG group (2547.18±1648.21pg/ mL vs. 3468.02±2497.69pg/mL, p<0.001), while the progesterone level was significantly higher (1.33±0.75 ng/mL vs. 1.01±0.52ng/mL, p=0.001). The numbers of retrieved and MII oocytes were significantly higher for the rFSH group compared with the hp-hMG group (16.82±10.95 vs. 13.25±9.66, p=0.02, and 13.22±9.13 vs. 9.76±7.11, p=0.005), while the maturity rates were comparable (p=0.103). Conclusions: Patients in the rFSH group had higher numbers of both retrieved and MII oocytes when undergoing elective FP.