title: Trends of menarcheal age in women in the reproductive age and menopause in Shanghai.
abstract: OBJECTIVE
  To explore the factors affecting menarcheal age by investigating two groups of women differing in age by 10-15 years in Shanghai.
  
  
  METHODS
  Data on 5,207 women were collected from January 2011 to May 2012: 2,151 women of reproductive age from the Obstetrical Department and 3,056 women in menopause from the Medical Center of the Sixth Hospital of Shanghai City. General data and data on menarcheal age and medical history were collected. The two groups were divided into subgroups from <10 to ≥20 years, i.e. 12 subgroups in total, respectively. SPSS 17.0 software was used to examine statistical differences.
  
  
  RESULTS
  The onset of menarcheal age of reproductive age women was 0.5 years earlier than that of menopause women (p < 0.05). In the early menarche age group (<13 years old), there were more reproductive age and high-educated women. Correlation analysis found the current body mass index in menopausal women was significantly negatively correlated with their menarcheal age (r = -0.033, p < 0.05).
  
  
  CONCLUSIONS
  There was a downward trend in menarcheal age in women of Shanghai and its surrounding areas. Economic environment and education background were the main factors affecting menarcheal age, and menarcheal age may be considered as a predictor of adult obesity.
authors.affiliation: Department of Gynecology, Sixth Affiliated People's Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Jin
authors.forename: Hongfang
authors.initials: H
authors.lastname: Shao
authors.forename: Minfang
authors.initials: M
authors.lastname: Tao
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D015992:Body Mass Index; D002648:Child; D002681:China; D004522:Educational Status; D004777:Environment; D005260:Female; D006304:Health Status; D006801:Humans; D008572:Menarche / Q000235:genetics / Q000502:physiology; D008593:Menopause; D008875:Middle Aged; D009765:Obesity; D012098:Reproduction; D012959:Socioeconomic Factors; D055815:Young Adult