Clinical characteristics, metabolic features, and phenotype of Chinese women with polycystic ovary syndrome: a large-scale case–control study

Aim The Rotterdam criteria extend the phenotypic spectrum of polycystic ovary syndrome (PCOS). The study was to investigate the clinical and biochemical features of a large-scale clinic based on the samples of Chinese women and to evaluate the value of Rotterdam criteria on Chinese PCOS women. Methods One thousand four hundred and four Chinese women were involved in our study, among whom, 719 cases were diagnosed as PCOS based on 2003 Rotterdam criteria, and 685 women without history of hyperandrogenism and with regular menstrual cycles were recruited as control. Clinical features, ultrasonographic (ovarian follicle number and volume), hormonal and metabolic parameters were commenced as outcome measures. Results Among 719 PCOS women, 6.1 % had hirsutism, 13.3 % had acne, 21.1 % had hyperandrogenism, 94.2 % had polycystic ovaries on ultrasonographic examination, and 88.6 % had menstrual abnormality. About one-third of the total PCOS patients were insulin resistant. The most frequent PCOS phenotype is the non-hyperandrogenic phenotype (O + P). Total testosterone, LH/FSH ratio, body mass index (BMI), and Ferriman and Gallwey scores (F–G) were all significantly higher in PCOS groups compared with non-PCOS group. Women with PCOS and obesity had higher serum testosterone, fasting insulin, longer menstrual cycle and larger ovarian follicle number, and LH/FSH ratio, estradiol or ovarian volume were similar between obese and normal BMI women. The LH level was statistically lower in the obese PCOS group. Conclusions Rotterdam criteria are generally applicable to Chinese population. Chinese women with PCOS showed lower rates of hyperandrogenemia, hirsutism, obesity, and insulin resistance. Obesity aggravates menstrual irregularity and increases the follicle number and serum total testosterone level.