PCOS patients meeting the trial criteria were enrolled from the Shanghai 10th People's Hospital. The contents of this study were introduced to them, and they were invited to participate in the study. We further evaluated the efficacy and safety of arginine in treating PCOS by implementing the L-arginine clinical intervention protocol, and conducting post-intervention follow-up, efficacy evaluation, laboratory tests, and fecal sample 16S rRNA sequencing.

In this study, we will enroll PCOS patients who meet the trial criteria from the Shanghai 10th People's Hospital, introduce the content of this study to them, and invite them to participate in the study. Perform laboratory tests for PCOS and collect baseline stool and blood samples. The clinical intervention program of L-arginine was implemented, and post-intervention follow-up, efficacy evaluation and laboratory examination were carried out. Stool and blood samples were collected after the intervention, and 16S rRNA sequencing was performed on stool samples before and after the intervention. To analyze whether PCOS-related clinical and laboratory indicators improved after L-arginine treatment of PCOS, and to analyze the changes in patients' microbiome before and after L-arginine treatment, to clarify the effectiveness and safety of L-arginine treatment of PCOS.

Inclusion Criteria:

• aged 18-45 years
• Diagnosis of PCOS with the Rotterdam diagnosis criteria (2003)

Exclusion Criteria:

• Pregnant women;
• Hyperthyroidism or hypothyroidism
• Severe liver and kidney function injury
• Cancer patients;
• Associated with severe infection, severe anemia, neutropenia and other blood system diseases;
• Have type 1 diabetes, single-gene mutated diabetes or other secondary diabetes;
• Patients with mental illness or intellectual disability;
• Have a long history of taking hormone therapy;
• Currently or recently participating in another clinical trial.