Association of miR-146aC>G, miR-149C>T, miR-196a2T>C, and miR-499A>G polymorphisms with risk of recurrent implantation failure in Korean women.

Objective: The aim of this study was to investigate the association of microRNA polymorphisms (miR-146aC>G, miR-149T>C, miR-196a2T>C, and miR-499A>G) in Korean patients with recurrent implantation failure (RIF).

Methods: We conducted a case-control study of 354 Korean women: 120 patients with RIF and 234 healthy controls with at least one live birth and no history of pregnancy loss.

Results: The combined miR-146aCG+GG/miR-196a2CC genotype was more frequent in patients than in controls (P<0.