title: Premenopausal factors influencing premature ovarian failure and early menopause.
abstract: OBJECTIVE
  We conducted this study to examine premenopausal risk factors associated with premature ovarian failure (POF) and early menopause (EM) among Korean women.
  
  
  METHODS
  A 73% of total women aged 30-69 at four districts in the KMCC (Korean Multi-center Cancer Cohort) was participated in this study during 2002-2003. We selected 137 POF and 281 EM cases who had menopause before age 40 and at age 40-44, respectively, and 1318 normal menopause (NM) controls that experienced menopause at age 45-60, and among them, selected idiopathic POF (n=84) and EM (n=261) after excluding surgical/medical menopause. We collected the information of premenopausal lifestyle and reproductive risk factors. Multivariate and polytomous logistic regression were used to estimate POF and EM risk and to differentiate POF and EM risk using ordinal and nominal scale.
  
  
  RESULTS
  Cigarette smoking was associated with an increased risk of idiopathic POF (OR=1.82 [1.03-3.23]), whereas oral contraceptive use was associated with a reduced risk of natural EM (OR=0.62 [0.43-0.90]). Idiopathic POF risk by both factors differed from idiopathic EM risk (p-nominal<0.05). Factors related to ovulation, such as later menarche, irregular menstruation and longer breast feeding cumulatively reduced the risk of natural EM and POF (p-ordinal<0.05). In analysis including medical and surgical menopause, lung tuberculosis, hysterectomy, past cancers, and lower number of deliveries before menopause were associated with POF.
  
  
  CONCLUSIONS
  Our findings indicate that etiology in POF development may partly differ from that in EM.
authors.affiliation: Department of Preventive Medicine, Konkuk University School of Medicine, Chungju, Republic of Korea.
authors.forename: Soung Hoon
authors.initials: SH
authors.lastname: Chang
authors.forename: Chung-Sik
authors.initials: CS
authors.lastname: Kim
authors.forename: Kun-Sei
authors.initials: KS
authors.lastname: Lee
authors.forename: Hyeongsu
authors.initials: H
authors.lastname: Kim
authors.forename: Sung Vin
authors.initials: SV
authors.lastname: Yim
authors.forename: Yun Jeong
authors.initials: YJ
authors.lastname: Lim
authors.forename: Sue Kyung
authors.initials: SK
authors.lastname: Park
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D015438:Health Behavior; D006801:Humans; D007723:Korea / Q000453:epidemiology; D008019:Life Style; D016015:Logistic Models; D008594:Menopause, Premature; D008875:Middle Aged; D016649:Primary Ovarian Insufficiency / Q000453:epidemiology*; D012307:Risk Factors; D016387:Women's Health