A panel of experts from The Endocrine Society recently released updated clinical practice guidelines for the diagnosis and treatment of polycystic ovary syndrome (PCOS). Because the pathogenesis of PCOS is still unclear and its clinical features are atypical, it has been one of the hot topics of discussion in recent years at major conferences in reproductive medicine and at the National Institutes of Health (NIH). Dr. Richard S. Legro of the Pennsylvania State University College of Medicine (leader of the PCOS guideline development expert panel) noted in a press release on the guidelines that the latest guidelines from the Endocrine Society will help clinicians and patients with PCOS gain a better understanding of this complex disease. Some of the guidelines suggest that clinicians can confirm the diagnosis in patients with typical symptoms but lacking positive hormone levels and ultrasound findings. For the diagnosis of adult PCOS, the guidelines recommend using the Rotterdam criteria, which require two of the following three criteria: hyperandrogenism, sporadic ovulation or anovulation, and polycystic ovarian changes. Other causes of hyperandrogenemia (such as thyroid disease, hyperprolactinemia, and atypical congenital adrenocortical hyperplasia) must also be excluded at the time of diagnosis. The panel said that the diagnostic criteria for adolescents and menopausal women are currently more controversial. Hormonal contraceptives are recommended as first-line treatment for adolescent patients with a proposed diagnosis of PCOS if there is a therapeutic need to improve symptoms related to acne, hirsutism and anovulation or for contraception. Because the combination of pregnancy in patients with PCOS leads to an increased risk of complications (e.g., gestational diabetes, preterm delivery, and preeclampsia), the panel recommends that BMI, blood pressure, and oral glucose tolerance tests be performed prior to pregnancy. BMI and abdominal circumference should be used as indicators of increased metabolic risk. Adolescents and adult women with PCOS are at increased risk for type 2 diabetes and impaired glucose tolerance, so OGTT should be routinely performed in these populations. Clomiphene citrate can be used as first-line treatment for infertile patients, and metformin is indicated for patients with metabolic disorders and/or abnormal blood glucose levels and to regulate their menstrual cycle.