title: A prospective study of symptomatic gallstones in women: relation with oral contraceptives and other risk factors.
abstract: OBJECTIVE
  To examine the relation between oral contraceptives (OCs), body mass index (BMI), weight change, alcohol use, parity, smoking, and symptomatic gallstones in women less than 45 years of age.
  
  
  METHODS
  In this prospective study, associations between the various self-reported exposures and symptomatic gallstones were assessed in 96,211 female United States nurses with 425 cases of gallstones, using multiple logistic regression.
  
  
  RESULTS
  We found little relation between ever-use of OCs and symptomatic gallstones (relative risk [RR] 1.2, 95% confidence interval [CI] 0.9-1.6), although there was a modest elevation in risk for long-term use (RR 1.5, 95% CI 1.0-2.2 for 10-14 years; RR 1.6, 95% CI 1.0-2.4 for 15 or more years). There was also an increased risk in current users of OCs (RR 1.6, 95% CI 1.1-2.4). The risk of symptomatic gallstones increased with increasing BMI and weight gain since age 18. Women with four or more births had an elevated risk of symptomatic gallstones (RR 2.0, 95% CI 1.3-3.2), and current cigarette smokers had a slightly higher risk than never-smokers (RR 1.3, 95% CI 1.0-1.7). The risk decreased with increasing alcohol intake.
  
  
  CONCLUSIONS
  We found no substantial increase in the risk of symptomatic gallstones among ever-OC users, although current and long-term users had somewhat elevated risks. Body mass index remains the strongest predictor of symptomatic gallstones among young women.
authors.affiliation: Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts.
authors.forename: F
authors.initials: F
authors.lastname: Grodstein
authors.forename: G A
authors.initials: GA
authors.lastname: Colditz
authors.forename: D J
authors.initials: DJ
authors.lastname: Hunter
authors.forename: J E
authors.initials: JE
authors.lastname: Manson
authors.forename: W C
authors.initials: WC
authors.lastname: Willett
authors.forename: M J
authors.initials: MJ
authors.lastname: Stampfer
mesh_terms: D000328:Adult; D000367:Age Factors; D000428:Alcohol Drinking; D015992:Body Mass Index; D002769:Cholelithiasis / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology; D015331:Cohort Studies; D016001:Confidence Intervals; D003276:Contraceptives, Oral / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008593:Menopause; D010298:Parity; D011446:Prospective Studies; D012044:Regression Analysis; D012306:Risk; D012307:Risk Factors; D012907:Smoking; D013997:Time Factors; D015430:Weight Gain
chemical_list: D003276:Contraceptives, Oral