MTHFR and endometriosis: The analysis of MTHFR polymorphism distribution according to endometriosis diagnosis showed a lower rate of MTHFR wild-type (22.6% vs. 39.9%, p = 0.0014) and a higher rate of MTHFR C677T homozygous polymorphism—A1298C wild-type in patients with endometriosis (24.5% vs. 15.8%, p = 0.0453) (Table 2).