An Argonaute (AGO) protein within the RNA-induced silencing complex binds a microRNA,
permitting the target mRNA to be silenced. We hypothesized that variations in AGO genes had the
possibility including affected the miRNA function and associated with recurrent pregnancy loss (RPL)
susceptibility. Especially, we were chosen the AGO1 (rs595961, rs636832) and AGO2 (rs2292779,
rs4961280) polymorphisms because of those polymorphisms have already reported in other diseases
excluding the RPL. Here, we conducted a case-control study (385 RPL patients and 246 controls)
to evaluate the association of four polymorphisms with RPL. We found that the AGO1 rs595961 AA
genotype, recessive model (P = 0.039; P = 0.043, respectively), the AGO1 rs636832 GG genotype, and
recessive model (P = 0.037; P = 0.016, respectively) were associated with RPL in women who had had
four or more consecutive pregnancy losses. The patients with the AGO1 rs636832 GG genotypes had
greater platelet counts (P = 0.023), while the patients with the AGO2 rs4961280 CA genotypes had less
homocysteine (P = 0.027). Based on these results, we propose that genetic variations with respect to
the AGO1 and AGO2 genotypes are associated with risk for RPL, and might serve as useful biomarkers
for the prognosis of RPL.