title: Organochlorine exposure and age at natural menopause.
abstract: BACKGROUND
  The effect of potential endocrine-modulating organochlorines on menopause has not been extensively examined.
  
  
  METHODS
  We evaluated the associations of plasma polychlorinated biphenyls (PCBs) and 1,1-dichloro-2,2-bis( -chlorophenyl)ethylene (DDE) with age at natural menopause. We analyzed data from 1407 women in a population-based, case-control study of breast cancer that was carried out in 1993-1996 in North Carolina.
  
  
  RESULTS
  The adjusted hazard ratio estimating the rate of onset of natural menopause was 1.4 (95% confidence interval = 0.9-2.1) for the top decile of DDE compared with values below the median. This association is similar in magnitude to the association between smoking and menopause (hazard ratio = 1.4 [1.1-1.9]). No association was seen with PCBs.
  
  
  CONCLUSIONS
  The suggested effect of DDE on timing of natural menopause encourages further research to corroborate these findings and evaluate potential mechanisms. Prospective studies, in which exposure measurements are taken before menopause, would be particularly useful.
authors.affiliation: Epidemiology Branch, National Institute of Environmental Health Sciences, Durham, NC, USA. cooper1@niehs.nih.gov
authors.forename: Glinda S
authors.initials: GS
authors.lastname: Cooper
authors.forename: David A
authors.initials: DA
authors.lastname: Savitz
authors.forename: Robert
authors.initials: R
authors.lastname: Millikan
authors.forename: Tse
authors.initials: T
authors.lastname: Chiu Kit
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D016022:Case-Control Studies; D003633:Dichlorodiphenyl Dichloroethylene / Q000009:adverse effects / Q000097:blood*; D004781:Environmental Exposure / Q000009:adverse effects; D005260:Female; D006801:Humans; D008593:Menopause / Q000097:blood; D008875:Middle Aged; D009657:North Carolina; D011078:Polychlorinated Biphenyls / Q000009:adverse effects / Q000097:blood*; D012307:Risk Factors
chemical_list: D003633:Dichlorodiphenyl Dichloroethylene; D011078:Polychlorinated Biphenyls