The cumulative live birth rate of recombinant follicle-stimulating hormone alfa verse urinary human follicle-stimulating hormone for ovarian stimulation in assisted reproductive technology cycles

Background Infertility remains a significant public health concern. An issue with controlled ovarian stimulation (COS) is the selection of an exogenous gonadotropin (Gn) regimen, which is mainly based on urinary follicle-stimulating hormone (uFSH), recombinant follicle-stimulating hormone alfa (rFSH-alfa), and human menopausal gonadotropin (HMG). In addition, most previous studies focused on the clinical pregnancy rates or live birth rates (LBR) per transfer cycle, but not on the cumulative live birth rate (CLBR) per started cycle. The CLBR, appears to be a more comprehensive and accurate universal measure of IVF treatment success. Therefore, this study aimed to compare the cumulative live birth rate (CLBR) between rFSH-alfa and uFSH regimens for ovarian stimulation. Methods This retrospective cohort study included patients who underwent assisted reproductive technology (ART) with gonadotropin-releasing hormone (GnRH) agonist long protocol between March 2009 and December 2018. Patients were grouped according to the Gn regimen received (rFSH-alfa or uFSH). The main outcome was CLBR, which defined as the first live birth following the use of all fresh and frozen embryos derived from a single COS cycle. Results A total of 1078 cycles were analyzed (314 with rFSH-alfa and 764 with uFSH). The rFSH-alfa group was characterized by a higher number of retrieved oocytes (13.3 vs. 11.0) and transferable embryos (5.0 vs. 4.0), a higher fresh embryo transfer rate (35.0% vs. 26.3%), and a higher multiple birth rate among the fresh embryo transfer cycles (8.2% vs. 2.5%) (P < 0.05). There were no differences in pregnancy rate (32.7% vs. 33.8%) and LBR (25.5% vs. 26.9%) per transfer cycle (P > 0.05). No significant difference was found in clinical outcomes among the frozen embryo transfer cycles (P > 0.05). The CLBR per started cycle in the rFSH-alfa group was higher than in the uFSH group (53.5% vs. 43.1%, P < 0.05). After adjustment, rFSH-alfa was independently associated with a higher CLBR (OR = 1.56; 95%CI = 1.18-2.05; P = 0.0018). Conclusions rFSH-alfa and uFSH have similar pregnancy rates and LBR per transfer cycle, rFSH-alfa might achieve more transferrable blastocysts and higher CLBR per started cycle compared to uFSH.

Automated summary

The study found that rFSH-alfa group had higher number of retrieved oocytes, transferable embryos, fresh embryo transfer rate, and multiple birth rate compared to the uFSH group. However, both groups had similar pregnancy rates and LBR per transfer cycle, with rFSH-alfa group achieving higher CLBR per started cycle. This suggests that rFSH-alfa might produce more transferrable blastocysts and higher overall success rates compared to uFSH.