Polycystic Ovary Syndrome (PCOS)
Diagnosis of PCOS
There is no specific test to definitively diagnose polycystic ovary syndrome. The diagnosis is one of exclusion, which means the doctor considers all signs and symptoms to rule out other possible disorders.14 A standard diagnostic assessment for PCOS includes a full medical history, at which time a doctor will consider irregular or absent periods, obesity, hirsutism (coarse facial and body hair), and poor breast development. During a physical exam, doctors typically look for physical signs of PCOS like acne, facial hair, male pattern baldness and acanthosis nigricans.
A pelvic or transvaginal ultrasound is used to detect "follicular arrest," or the development of small (5–7 mm) follicles that never reach the preovulatory size of 16 mm or more. Though not all women with PCOS have polycystic ovaries (PCO), nor do all women with ovarian cysts have PCOS,21 ultrasonographic scanning has substantially broadened the phenotypic spectrum of PCOS.14
Diagnostic criteria published by the Androgen Excess Society in 2006 require the presence of clinical or biochemical hyperandrogenism, with either menstrual dysfunction or polycystic ovarian morphology (PCOM), which are detected via transvaginal ultrasonography.21
Blood work is used to measure the levels of several hormones and to exclude the many possible causes of menstrual abnormalities or androgen excess that mimic PCOS. Along with tests used to measure elevated androgen levels, doctors may look for high levels of luteinizing hormones (LH) or an elevation in the ratio of LH to follicle stimulating hormone (FSH), prolactin, thyroid stimulating hormone (TSH), 17-hydroxyprogesterone, testosterone and DHEA-S. Other associated conditions such as high levels of glucose, insulin, cholesterol and triglycerides, as well as insulin resistance may also be assessed.22
Some doctors now screen for high levels of anti-Müllerian Hormone (AMH) since it is considered a potential diagnostic marker for PCOS.23,24 AMH is a protein released by cells that are involved with the growth of the egg follicle. AMH levels correlate with the number of antral follicles (small follicles that are 2 to 8 mm in size and appear in the beginning of the menstrual cycle) found on the ovary; the higher the antral follicle count, the higher the AMH levels.25 Women with PCOS typically have a high number of antral follicles; they have correspondingly high AMH levels as well.26