Can the FMR1 (Fragile X) Gene Serve As Predictor of Response to Ovarian Stimulation?

Because triple GGG repeats on FMR1 correlate with anti-Mullerian hormone, repeats may also correlate with clinical outcomes. In 55 in vitro fertilization patients, repeats, corrected for gonadotropin dosage, were, therfore, correlated to oocytes. Patients were stratified by <35 and >= 35 repeats, and by age to <38 or >= 38 years. Less than 35 (but not >= 35) repeats demonstrated significantly lower anti-Mullerian hormone at ages >= 38 than at <38 years (P < .05). In >38 years, anti-Mullerian hormone was not affected by repeats. In <38 years, with <35 repeats (though not with >= 35), required significantly less gonadotropins than >= 38 (P < .05). In <38 years (though not >= 38), those with <35 repeats produced significantly more oocytes than women with >= 35 repeats (P = .006). In <38 years, retrieved oocytes were inversely related to repeats, adjusted for gonadotropin dosage (P = .03). This supports FMR1 testing as useful in fertility practice and suggests why response rates to increasing stimulation with gonadotropins may vary.