Obesity is the most potential risk of threat to health of populations. There is a major impact of obesity on the PCOS related disorders. Insulin resistance and distribution of adipose tissue were thought to be the important risk factors of cardiovascular and metabolic syndrome. To treat PCOS patients properly,Wan-Fang hospital had established a specific medical team. The investigators recently published in "Fertility and Sterility" about the clinical presentation of androgen excess in Taiwanese women. Hirsutism is much less prevalence (30%) in Taiwanese PCOS women than that previous reported (65-80%) in theWestern women. It is important to know that some clinical presentation of PCOS might have ethic variance. Insulin resistance was reported as another candidate that might have ethic variance. The investigators had reported about 40% women in PCOS women were obese, it is similar with previous literature reported. Obesity is a major factor that could be controlled during the treatment of PCOS.Weight reduction is one of our methods in PCOS treatment. The progressive results for obese PCOS women would be facing the risks of diabetes and metabolic syndrome. The investigators thought like to evaluate the benefit of weight reduction program to the prognosis of obese women with PCOS.