Statistical Analysis
Data analysis was performed using SPSS (version 20; SPSS Inc). Continuous variables of clinical characteristics were displayed as mean±standard deviation and compared by t-test. Parameters not normally distributed were presented as median(inter-quartile range) and compared by nonparametric test. Correlation between different variables was analyzed by Pearson correlation analysis and linear regression analysis. Receiver operating characteristic (ROC) curve were used for the independent predictive analysis. Binary logistic regression was used to assess the relationships between variables and incidence of PCOS. All values of P < 0.05 for two-side tests were considered statistically significant.