Early decline in functional ovarian reserve in young women with low (CGGn < 26) FMR1 gene alleles.

Mouse fmr1 models, and recent cross-sectional human data, suggest that different triple CGGn ranges of the fragile X mental retardation 1 (FMR1) gene are associated with variations in ovarian aging and infertility treatment outcomes. The FMR1 mutation affecting reproductive function most negatively in humans is the so-called low mutation, characterized by CGGn < 26. We here present a first longitudinal study of selected young women with normal functional ovarian reserve (FOR).