In the comparison between PCOS-HB and PCOS-LB groups, bilirubin was significantly related to BMI, SHBG, Alistipes, Eubacterium, Ruminococcaceae, and 4-chlorophenol with LH, E2, Alistipes, Holdemania, and Oscillibacter and hydrocinnamic acid with free triiodothyronine (FT3). Here, PLOD1 is linked to polycystic ovary syndrome.