Polycystic ovary syndrome is one of the main diseases leading to infertility in women of childbearing age. In addition to endocrine and reproductive dysfunction, it is often accompanied by significant metabolic abnormalities, which seriously affect long-term health and quality of life. Our preliminary research found that 68% of PCOS patients have significantly increased branched chain amino acid content, accompanied by a decrease in clinical pregnancy rate and an increase in miscarriage rate, which poses challenges to the diagnosis and treatment of PCOS. Based on this, we propose a new PCOS typing strategy that uses the concentration of branched chain amino acids as an evaluation indicator to diagnose high branched chain amino acid PCOS, where the serum BCAA concentration is higher than 405 μ Mol/L is diagnosed as high branched chain amino acid PCOS. According to the different degrees of elevation of branched chain amino acids, they are further divided into common type and ultra-high type, and the impact of different concentrations of branched chain amino acids on pregnancy outcomes, pregnancy complications, and newborns after assisted reproductive technology is analyzed; Based on the typical clinical and metabolic phenotypes of high branched chain amino acid type PCOS patients, corresponding intervention strategies are formulated. By analyzing the clinical pregnancy outcomes, pregnancy complications, and neonatal conditions of patients in the combination intervention group (protein restricted diet combined with vitamin D supplementation) and the conventional treatment group, safe and effective intervention methods are determined.

Based on this, we propose a new PCOS typing strategy that uses the concentration of branched chain amino acids as an evaluation indicator to diagnose high branched chain amino acid PCOS, where the serum BCAA concentration is higher than 405 μ Mol/L is diagnosed as high branched chain amino acid PCOS. According to the different degrees of elevation of branched chain amino acids, they are further divided into common type and ultra-high type, and the impact of different concentrations of branched chain amino acids on pregnancy outcomes, pregnancy complications, and newborns after assisted reproductive technology is analyzed; Based on the typical clinical and metabolic phenotypes of high branched chain amino acid type PCOS patients, corresponding intervention strategies are formulated. By analyzing the clinical pregnancy outcomes, pregnancy complications, and neonatal conditions of patients in the combination intervention group (protein restricted diet combined with vitamin D supplementation) and the conventional treatment group, safe and effective intervention methods are determined.

Inclusion Criteria:

The included population is PCOS patients who are seeking their first IVF treatment at the Reproductive Medicine Center of Peking University Third Hospital, aged 20-40 years old. PCOS diagnosis meets two of the following three criteria based on the 2003 Rotterdam criteria: clinical manifestations of oligomenorrhea and/or amenorrhea, hyperandrogenism or hyperandrogenism (hirsutism, acne, etc.), PCO like changes in the ovaries under ultrasound, while excluding diseases such as hyperprolactinemia, congenital adrenal hyperplasia, Cushing syndrome, and androgen secreting tumors. All selected subjects have no medical history of taking steroid drugs within 3 months.

Exclusion Criteria:

1) Refusing to sign informed consent or unable to follow up on time; 2) Severe complications requiring cessation of treatment (>2 weeks) or termination of treatment; 3) Patients should take vitamin D orally before enrollment (baseline data still needs to be recorded for later statistical analysis); 4) Any unstable or medical condition that affects patient safety and research compliance. 5) Male partners have severe male infertility factors; 6) Patients undergoing embryo analysis using pre implantation genetic testing techniques (PGT-A/SR/M).