1. Basal body temperature measurement Basal body temperature measurement is required for irregular menstruation or dribbling, which is mostly monophasic. 2. Blood endocrine examination during the early follicular phase (day 2-4 of the menstrual cycle) (in amenorrheic patients without a dominant follicle on vaginal ultrasound can be examined at any time), showing: (1) hyperandrogenemia: hyperandrogenism is the basic endocrine feature of PCOS, and testosterone (T) is moderately elevated. However, 20% to 30% of patients with PCOS do not have elevated androgens. (2) Hyperprolactinemia: about 12% of PCOS patients have moderate elevation of prolactin (<50 μg/L). (3) Urinary 17-hydroxyl and 17-ketosteroid measurements may be slightly elevated or normal, if significantly elevated suggest hyperadrenalism. 4.Oral glucose tolerance test (OGTT) and insulin release test usually take 75g of glucose orally, draw blood in the morning on an empty stomach, and draw blood again 1 hour and 2 hours after taking glucose to measure the value of glucose and insulin in blood. 5, ultrasound ultrasound PCO is a clinical sign, not equal to PCOS, but in practice, the ultrasound diagnosis of PCOS has jumped to a very important position. Vaginal ultrasound (transrectal ultrasound for unmarried non-sexual patients) by an experienced physician is advocated to detect ovarian morphology. The new diagnostic ultrasound criteria for polycystic ovaries are 12 or more follicles of 2-9 mm diameter in one or both ovaries and/or an ovarian volume greater than 10 ml. The diagnosis is made when the follicles in one ovary meet these criteria. 6. Diagnostic scraping is performed several days before menstruation or within 24 hours of menstrual flow for endometrial biopsy, showing endometrium in proliferative phase or overgrowth without secretory phase changes. It is advocated that patients >35 years old should be routinely scraped for early detection of endometrial atypical hyperplasia or endometrial cancer. 7. Laparoscopic examination can reveal polycystic enlargement of both ovaries with thickened grayish peritoneum and no ovulatory signs (ovulatory hole, corpus luteum or blood body). Due to the widespread use of vaginal ultrasound, laparoscopy is not used as a diagnostic tool for PCOS, but rather as a therapeutic tool.