DPP4 and polycystic ovary syndrome: Clinical reproductive outcomes confirmed the potential of the sitagliptin therapy, as among the 33 patients included, 31 achieved live births, and the clinical pregnancy rate and live birth rate in the treatment group (PCOS + S) were significantly higher than before sitagliptin treatment (Fig. 9A and B, AUC of ROC in ASCL4, TFR1, GPX4, and DPP4 = 1.000, 0.774, 0.919, 0.903).