Can the FMR1 (Fragile X) gene serve as predictor of response to ovarian stimulation?

Because triple CGG repeats on FMR1 correlate with anti-Müllerian hormone, repeats may also correlate with clinical outcomes. In 55 in vitro fertilization patients, repeats, corrected for gonadotropin dosage, were, therefore, correlated to oocytes. Patients were stratified by <35 and ĝ‰¥35 repeats, and by age to <38 or ĝ‰¥38 years. Less than 35 (but not ĝ‰¥35) repeats demonstrated significantly lower anti-Müllerian hormone at ages ĝ‰¥38 than at <38 years ( P <.05). In >38 years, anti-Müllerian hormone was not affected by repeats. In <38 years, with <35 repeats (though not with ĝ‰¥35), required significantly less gonadotropins than ĝ‰¥38 ( P <.05). In <38 years (though not ĝ‰¥38), those with <35 repeats produced significantly more oocytes than women with ĝ‰¥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.