Clinical Research Directory

Inclusion Criteria: * Female participants aged 14 to 45 years * Diagnosis of polycystic ovary syndrome (PCOS) * For adult participants, PCOS diagnosed according to the 2023 international evidence-based guideline. After exclusion of related disorders, diagnosis is based on ovulatory dysfunction and/or irregular menstrual cycles together with clinical hyperandrogenism, biochemical hyperandrogenism, or polycystic ovarian morphology on ultrasound where appropriate * For adolescent participants, PCOS diagnosed according to adolescent-specific recommendations. After exclusion of related disorders, both ovulatory dysfunction and/or irregular menstrual cycles and clinical or biochemical hyperandrogenism are required * Irregular menstrual cycles are defined as follows: more than 1 year and less than 3 years after menarche, menstrual cycles shorter than 21 days or longer than 45 days; more than 3 years after menarche to perimenopause, menstrual cycles shorter than 21 days or longer than 35 days, or fewer than 8 cycles per year; any cycle longer than 90 days more than 1 year after menarche; or primary amenorrhea by age 15 years or more than 3 years after thelarche * No use within 3 months before blood sampling of anticoagulant drugs, procoagulant drugs, oral contraceptives, or other medications that may affect sex hormones, insulin, glucose metabolism, or coagulation function Exclusion Criteria: * Confirmed pregnancy * Hematologic disease * History of malignant tumor * Use of medications within 12 weeks before enrollment that may interfere with study assessments * Disorders that may cause hyperandrogenism or ovulatory dysfunction, including congenital adrenal hyperplasia, Cushing syndrome, functional hypothalamic amenorrhea, thyroid disease, hyperprolactinemia, or primary ovarian insufficiency * Disorders that may affect protein C or protein S levels, including antiphospholipid syndrome, liver disease, or tumor-related conditions * In adolescents, polycystic ovarian morphology alone will not be used to establish the diagnosis of PCOS