Polycystic ovary syndrome (PCOS) is an extremely common disorder in women of reproductive age. Diagnosis of PCOS is principally based on clinical and physical findings. Diagnostic criteria and PCOS definitions used by clinicians and researchers are almost as heterogeneous as the syndrome. Of those diagnosed with PCOS using the 2003 Rotterdam criteria, 61% fulfilled 1990 NIH criteria for unexplained hyperandrogenic chronic anovulation. The patient populations with the new phenotypes had less severe ovulatory dysfunction and less androgen excess than patients diagnosed using the 1990 NIH criteria. These findings might be common across all female populations with PCOS, whether in Oriental or Occidental countries. Data for clinical hyperandrogenism indicated that the prevalence of hirsutism in Taiwanese PCOS women is lower than that for Caucasians/Western women.
The extent of metabolic abnormalities in women with PCOS may vary with phenotype, age and ethnicity. Obesity represents a major risk factor for metabolic syndrome and insulin resistance. Approximately 40-50% of all women with PCOS are overweight or obese. Obese subjects with PCOS had a higher risk of developing oligomenorrhea, amenorrhea and biochemical hyperandrogenemia than non-obese women with PCOS. Moreover, obese women with PCOS had significantly more severe insulin resistance, lower serum LH levels, and lower LH-to-FSH ratios than non-obese women with PCOS. PCOS women in Taiwan presented with higher LH-to-FSH ratio and lower insulin resistance than PCOS women in Western Countries. However, the average body mass index (BMI) was significantly lower in Taiwanese PCOS women than Western women, which might partially explain the difference between these two populations in terms of clinical and biochemical presentations.
To further document the ethnic variation between women with PCOS in Taiwan and Western, the effect of obesity on the diagnosis and clinical presentations of PCOS-related syndromes should not be neglected in future studies. Therefore, the investigators plan to do this prospective study for evaluation the clinical and biochemical presentation of Taiwanese women with PCOS.