Meanwhile, both methylation level of CpG 1 in the ESRα gene and progesterone were positively related to increased risk of IFG, and they have combined effects on IFG and T2DM, indicating that maintaining low levels of CpG 1 methylation of ESRα gene and progesterone could decrease the risk of glucose metabolic disorders. This evidence concerns the gene ESR1 and type 2 diabetes mellitus.