Objective: The aim of this study was to investigate whether N680S FSHR polymorphism has a predictive value for the ovarian response to stimulation with gonadotropins and cycle outcome in our egg donor program.
Methods: The oocyte donor candidates were selected according to the Instituto Bernabeu egg donation program requirements and ASRM and ESHRE guidelines for oocyte donation. The FSHR polymorphism N680S was studied in 145 oocyte donors. All donors underwent controlled ovarian hyperstimulation (COH) (n=355) using urinary follicle-stimulating hormone in a GnRH antagonist protocol and receiving a GnRH agonist triggering. The main outcome measures were oocyte yield, days of stimulation, gonadotropin doses, biochemical pregnancy, ongoing pregnancy, and miscarriage rates.
Results: Significant differences were reported in the antral follicle count (16.5 ± 5.0 for NN, 14.5 ± 4.7 for NS, and 14.1 ± 3.8 for SS), number of eggs retrieved (21.5 ± 9.2 for NN, 18.5 ± 8.2 for NS, and 19.8 ± 8.9 for SS), and gonadotropin doses (2098.5 ± 639.4 IU for NN, 2023 ± 490.1 IU for NS, and 2149.5 ± 552.3 IU for SS) between the genotypes. The clinical outcome was not affected by the N680S polymorphism of the FSHR gene in the egg donors.
Conclusion: In a population of fertile egg donors, the FSHR gene polymorphism at position 680 is associated with different ovarian responses to COH. The genotype of the FSHR gene is an important factor for determining the prognosis of the COH cycles in normo-ovulatory fertile women.