Follicle-stimulating Hormone Receptor Polymorphisms in Women with Normogonadotropic Anovulatory Infertility

Objective: To assess the incidence of different FSH receptor genotypes in normogonadotropic anovulatory infertile women (World Health Organization class II) and normo-ovulatory controls and to correlate these genotypes with baseline characteristics and ovarian responsiveness during ovulation induction.

Design: Cross-sectional study.

Setting: University hospital.

Patient(s): Thirty normo-ovulatory controls and 148 normogonadotropic anovulatory infertile women.

Intervention(s): All participants underwent a standardized evaluation that included cycle history, body mass index measurement, and transvaginal ultrasonography of ovaries. Fasting blood samples were obtained for endocrine evaluation. Ovarian responsiveness to FSH in normogonadotropic anovulatory infertile women was assessed during ovulation induction, and DNA was analyzed to determine the FSH receptor genotype.

Main Outcome Measure(s): Prevalence of FSH receptor polymorphisms, baseline serum FSH levels, amount of FSH administered, duration of stimulation, and ovarian response dose.

Result(s): The Thr/Thr 307 genotype was significantly less prevalent (52% vs. 23%) and the Ser/Ser 680 polymorphism was significantly more prevalent (40% vs. 16%) in patients compared with controls. Normogonadotropic anovulatory infertile women with the Ser/Ser 680 polymorphism presented with higher median FSH serum levels (5.2 IU/L [range, 2.4-9.7 IU/L]) than did those with the Asn/Asn 680 (4.6 IU/L [range, 1.4-5.8 IU/L) and Asn/Ser 680 (4.5 IU/L [range, 1.8-9.7 IU/L) variants. However, ovarian responsiveness to FSH was similar among anovulatory women with the various polymorphisms.

Conclusion(s): Normogonadotropic anovulatory infertile patients have a different FSH receptor genotype than do normo-ovulatory controls. Although this characteristic is associated with increased baseline FSH serum levels, altered ovarian sensitivity to exogenous FSH during ovulation induction could not be established.