title: A prospective study of pregravid determinants of gestational diabetes mellitus.
abstract: BACKGROUND
  Gestational diabetes mellitus (GDM) affects 3% to 5% of pregnancies. Knowledge of risk factors for GDM is needed to identify possible preventive strategies.
  
  
  OBJECTIVE
  To assess whether recognized determinants of noninsulin-dependent diabetes mellitus also may be markers for increased risk of GDM.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  The Nurses' Health Study II, which involves female US nurses aged 25 to 42 years at entry.
  
  
  METHODS
  The analyses included 14613 women without previous GDM or other known diabetes who reported a singleton pregnancy between 1990 and 1994. Of these women, 722 (4.9%) reported a new diagnosis of GDM.
  
  
  METHODS
  Self-report of GDM, validated by medical record review in a subset.
  
  
  RESULTS
  In multivariate analyses including age, pregravid body mass index (BMI), and other GDM risk factors, the risk for GDM increased significantly with increasing maternal age (P for trend, <.01) and family history of diabetes mellitus (relative risk, 1.68; 95% confidence interval [CI], 1.39-2.04). Relative risks for GDM were 2.13 (95% CI, 1.65-2.74) for pregravid BMI of 25 to 29.9 kg/m2 and 2.90 (95% CI, 2.15-3.91) for BMI of 30 kg/m2 or more (vs BMI of <20 kg/m2). Risk for GDM increased with greater weight gain in early adulthood, and it also increased among nonwhite women. Pregravid current smokers had a relative risk for GDM of 1.43 (95% CI, 1.14-1.80), and pregravid vigorous exercise was associated with a nonsignificant reduction in GDM risk.
  
  
  CONCLUSIONS
  Advanced maternal age, family history of diabetes mellitus, nonwhite ethnicity, higher BMI, weight gain in early adulthood, and cigarette smoking predict increased GDM risk. These observations may facilitate the identification of women at particular risk for GDM and suggest potential strategies for reducing this risk even before a woman becomes pregnant, such as avoiding substantial weight gain and smoking.
authors.affiliation: Section for Clinical Epidemiology, Division of General Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Mass, USA.
authors.forename: C G
authors.initials: CG
authors.lastname: Solomon
authors.forename: W C
authors.initials: WC
authors.lastname: Willett
authors.forename: V J
authors.initials: VJ
authors.lastname: Carey
authors.forename: J
authors.initials: J
authors.lastname: Rich-Edwards
authors.forename: D J
authors.initials: DJ
authors.lastname: Hunter
authors.forename: G A
authors.initials: GA
authors.lastname: Colditz
authors.forename: M J
authors.initials: MJ
authors.lastname: Stampfer
authors.forename: F E
authors.initials: FE
authors.lastname: Speizer
authors.forename: D
authors.initials: D
authors.lastname: Spiegelman
authors.forename: J E
authors.initials: JE
authors.lastname: Manson
mesh_terms: D000328:Adult; D015992:Body Mass Index; D003924:Diabetes Mellitus, Type 2; D016640:Diabetes, Gestational / Q000453:epidemiology* / Q000517:prevention & control; D005260:Female; D006801:Humans; D016015:Logistic Models; D008423:Maternal Age; D015999:Multivariate Analysis; D011247:Pregnancy; D011446:Prospective Studies; D012307:Risk Factors; D012907:Smoking; D015430:Weight Gain