Influence of follicle-stimulating hormone receptor (FSHR) Ser680Asn polymorphism on ovarian function and in-vitro fertilization outcome: A meta-analysis

BackgroundA common follicle-stimulating hormone (FSH) receptor (or FSHR) polymorphism Ser680Asn (rs6166) was found to be associated with altered ovarian response in women undergoing in-vitro fertilization. To further investigate such an association, a meta-analysis was conducted.MethodsA PubMed literature search was conducted to identify all cohort studies investigating such a relationship. The following parameters—basal FSH levels, total FSH doses, oocytes retrieved, and pregnancy rates—were used to evaluate the ovarian function, its response to exogenous FSH and in-vitro fertilization and intracytoplasmic sperm injection outcome.ResultsA total of 1421 cases were collected from eight studies. Of them, a significantly lower basal FSH level was observed in patients harboring Asn/Asn (NN) genotype than those carrying the Ser/Ser (SS) genotype both in Asian (WMD: − 2.57 mIU/ml, 95% CI: − 2.96 to − 2.19, P < 0.0001) and Caucasian retrospective groups (WMD: − 1.86 mIU/ml, 95%CI: − 2.07 to − 1.66, P < 0.0001) with no heterogeneity. Moreover, carriers of the SS tended to require greater FSH doses than NN (WMD: −268.82 IU, 95% CI: − 561.28 to 23.63, P = 0.07). Other parameters, such as oocytes retrieved and pregnancy rate, were not significantly different between the groups.ConclusionCarriers of the SS variant have slightly higher basal FSH levels, tending to require higher doses of exogenous FSH for stimulation.