INS and diabetes mellitus: Congruent to our results, a cross-sectional study conducted in a rural Chinese population found positive associations of progesterone with fasting glucose, HbA1c, and an increased risk of prevalent pre-diabetes and T2D in men and women.8 Furthermore, in the study of Jiang et al8 in men and women, progesterone was inversely associated with HOMA-2β, an index of β-cell function, but not with fasting insulin as seen among men in the present study.