Compared to the wild-type genotype AA, mutant homozygote genotype AC had a 2.142 times higher risk of PCOS, and CC had 3.755 times higher risk of PCOS, which showed that the effect size was stronger for each additional risk allele C. In agreement with our study, a recent meta-analysis demonstrated that MTHFR A1298C was associated with PCOS susceptibility [31]. Here, MTHFR is linked to polycystic ovary syndrome.