PYCR2 and polycystic ovary syndrome: Univariate Cox regression analysis, followed by LASSO regression identified 10 key metabolism-related proteins significantly associated with reproductive outcomes in PCOS: ACSL5, ANPEP, CYB5R3, ENOPH1, GLS, GLUD1, LDHB, PLCD1, PYCR2, and PYCR3.