title: Bilateral oophorectomy is not associated with increased mortality: the California Teachers Study.
abstract: OBJECTIVE
  To investigate the effect of surgical menopause due to bilateral oophorectomy on mortality, in light of evidence that bilateral oophorectomy among premenopausal women rapidly reduces endogenous hormone levels, thereby modifying risks of cardiovascular disease and breast cancer.
  
  
  METHODS
  The California Teachers Study (CTS) is a prospective cohort study of 133,479 women initiated in 1995-1996 through a mailed, self-administered questionnaire. Relative risks and 95% confidence intervals (CI) were estimated using Cox proportional hazards regression.
  
  
  METHODS
  None.
  
  
  METHODS
  California Teachers Study participants who, at baseline, reported having surgical menopause due to bilateral oophorectomy (n = 9,785), were compared with participants with natural menopause (n = 32,219).
  
  
  METHODS
  None.
  
  
  METHODS
  We investigated whether bilateral oophorectomy was associated with all-cause, cardiovascular, or cancer mortality, overall and by menopausal hormone therapy use status.
  
  
  RESULTS
  Among participants aged <45 years at menopause, multivariable relative risks were 0.86 (95% CI, 0.74-1.00), 0.85 (95% CI, 0.66-1.11), and 0.91 (95% CI, 0.67-1.23) for all-cause mortality, cardiovascular mortality, and cancer mortality, respectively. Among participants with an age at menopause of ≥45 years, multivariable relative risks were 0.87 (95% CI, 0.80-0.94), 0.83 (95% CI, 0.71-0.96), and 0.84 (95% CI, 0.72-0.98) for all-cause, cardiovascular, and cancer mortality, respectively. The association between bilateral oophorectomy and mortality did not differ by baseline status of hormone therapy use.
  
  
  CONCLUSIONS
  Surgical menopause due to bilateral oophorectomy vs. natural menopause does not increase all-cause, cardiovascular, or cancer mortality.
authors.affiliation: Division of Cancer Etiology, Department of Population Sciences, Beckman Research Institute, City of Hope, Duarte, California 91010, USA.
authors.forename: Lei
authors.initials: L
authors.lastname: Duan
authors.forename: Xinxin
authors.initials: X
authors.lastname: Xu
authors.forename: Corinna
authors.initials: C
authors.lastname: Koebnick
authors.forename: James V
authors.initials: JV
authors.lastname: Lacey
authors.forename: Jane
authors.initials: J
authors.lastname: Sullivan-Halley
authors.forename: Claire
authors.initials: C
authors.lastname: Templeman
authors.forename: Sarah F
authors.initials: SF
authors.lastname: Marshall
authors.forename: Susan L
authors.initials: SL
authors.lastname: Neuhausen
authors.forename: Giske
authors.initials: G
authors.lastname: Ursin
authors.forename: Leslie
authors.initials: L
authors.lastname: Bernstein
authors.forename: Katherine D
authors.initials: KD
authors.lastname: Henderson
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000401:mortality*; D002140:California / Q000453:epidemiology; D002318:Cardiovascular Diseases / Q000401:mortality*; D005178:Faculty / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008875:Middle Aged; D009369:Neoplasms / Q000401:mortality*; D010052:Ovariectomy / Q000401:mortality*; D017698:Postmenopause; D017697:Premenopause; D011446:Prospective Studies; D012307:Risk Factors; D011795:Surveys and Questionnaires
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