title: Comparison of the phenotype of Chinese versus Dutch Caucasian women presenting with polycystic ovary syndrome and oligo/amenorrhoea.
abstract: BACKGROUND
  Polycystic ovary syndrome (PCOS) is a complex disorder with variable prevalence and clinical presentation in different populations, which may be mediated by geographical and ethnic background.
  
  
  METHODS
  We performed a comparison of phenotypic characteristics between 547 Chinese and 427 Dutch women with PCOS and oligo/amenorrhoea attending University Reproductive Centers in China and the Netherlands.
  
  
  RESULTS
  Chinese women presenting with a clinical diagnosis of PCOS were observed to have a higher incidence of hyperandrogenism (HA) (P < 0.001) and amenorrhoea (P < 0.001) compared with Dutch women, but no difference was observed in the incidence of polycystic ovaries (PCOs). Using population-specific cut-off values, Chinese women with PCOS demonstrated a higher incidence of increased BMI (P < 0.001), waist circumference (WC) (P < 0.001) and waist-hip ratio (P < 0.001) than Dutch women. In both groups, HA was associated with increased age, fasting insulin, homeostasis model assessment of insulin resistance (HOMA-IR) and serum LH while PCOs correlated with BMI, WC, HOMA-IR, fasting insulin and elevated total testosterone. Associations specific for ethnic background were found between LH and HA, and between both BMI and HOMA-IR, and PCOs.
  
  
  CONCLUSIONS
  Reproductive and metabolic characteristics differed between the two ethnic groups. Chinese women were found to present more frequently with a phenotype associated with increased risk of metabolic complications later in life, compared with Dutch Caucasian women. Ethnicity seems to determine part of the specific phenotypical presentation of PCOS.
authors.affiliation: Department of Reproductive Medicine and Gynecology,  University Medical Center Utrecht, Utrecht,  The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Guo
authors.forename: Z J
authors.initials: ZJ
authors.lastname: Chen
authors.forename: M J E
authors.initials: MJ
authors.lastname: Eijkemans
authors.forename: A J
authors.initials: AJ
authors.lastname: Goverde
authors.forename: B C J M
authors.initials: BC
authors.lastname: Fauser
authors.forename: N S
authors.initials: NS
authors.lastname: Macklon
mesh_terms: D000367:Age Factors; D000568:Amenorrhea / Q000150:complications / Q000208:ethnology* / Q000378:metabolism; D015992:Body Mass Index; D002681:China / Q000208:ethnology; D005260:Female; D006801:Humans; D015994:Incidence; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000208:ethnology; D009426:Netherlands / Q000208:ethnology; D009839:Oligomenorrhea / Q000150:complications / Q000208:ethnology* / Q000378:metabolism; D010641:Phenotype; D011085:Polycystic Ovary Syndrome / Q000150:complications / Q000208:ethnology* / Q000378:metabolism; D055105:Waist Circumference; D049629:Waist-Hip Ratio; D044465:White People / Q000208:ethnology
chemical_list: D007328:Insulin