title: Parity and increased risk of insulin resistance in postmenopausal women: the 2010 Korean National Health and Nutrition Examination Survey.
abstract: OBJECTIVE
  The objective of this study was to assess the association between parity and insulin resistance in nondiabetic, postmenopausal women.
  
  
  METHODS
  This cross-sectional study was conducted using data from the 2010 Korean National Health and Nutrition Examination Survey administered by the Korean Ministry of Health and Welfare. A total of 1,243 nondiabetic postmenopausal women were included in this study and subdivided into three groups according to parity (1-2, 3-4, and ≥5 live births). Insulin resistance was measured using the homeostasis model assessment of insulin resistance (HOMA-IR) index. The relationship between parity and insulin resistance was investigated using analysis of covariance.
  
  
  RESULTS
  HOMA-IR showed a positive relationship with parity. Mean HOMA-IR (geometric mean and 95% CI) increased according to increasing parity group (1-2, 3-4, and ≥5 live births) after adjustment for age, smoking, alcohol consumption, exercise, education, income, and body mass index as follows: 2.1 (2.0-2.2) < 2.2 (2.1-2.3) < 2.5 (2.2-2.8) (P = 0.040 and P for trend = 0.012). In addition, this positive association was more apparent when insulin resistance was accompanied by obesity. The mean parity of the obese and insulin-resistant group was significantly higher than that of the nonobese insulin-sensitive group (3.6 ± 0.1 vs 3.2 ± 0.1, P = 0.047).
  
  
  CONCLUSIONS
  Our study provides the first evidence that parity is significantly associated with insulin resistance in nondiabetic postmenopausal women. Further prospective longitudinal studies are needed to confirm the impact of parity on insulin resistance.
authors.affiliation: 1Department of Obstetrics and Gynecology, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea 2Department of Obstetrics and Gynecology, St. Vincent's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: Jin Hwi
authors.initials: JH
authors.lastname: Kim
authors.forename: Sung Jong
authors.initials: SJ
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000502:physiology*; D008875:Middle Aged; D009749:Nutrition Surveys; D009765:Obesity / Q000503:physiopathology; D010298:Parity / Q000502:physiology*; D017698:Postmenopause / Q000502:physiology*; D011247:Pregnancy; D056910:Republic of Korea; D012307:Risk Factors
chemical_list: D007328:Insulin