title: Risk of endometriosis in 11,000 women with celiac disease.
abstract: BACKGROUND
  Endometriosis is a common cause of infertility. Whereas celiac disease (CD) is present in ~1% of individuals in Western Europe, the prevalence in women undergoing investigation for infertility is often >2%. Still, the relationship between CD and endometriosis is unclear.
  
  
  METHODS
  We identified 11 097 women with CD (Marsh 3: villous atrophy) through biopsy data from all 28 pathology departments in Sweden. Biopsies had been performed between 1973 and 2008. Data on inpatient and outpatient diagnoses of endometriosis were retrieved from the National Patient Register. We then used the Cox regression to estimate the hazard ratios (HRs) for endometriosis in women with CD to compare with those in 54 992 age-matched control women.
  
  
  RESULTS
  During the follow-up, 118 individuals with CD and 399 matched controls developed endometriosis. Hence, patients with CD were at increased risk of subsequent endometriosis [HR = 1.39; 95% confidence interval (CI) = 1.14-1.70]. The absolute risk of endometriosis in patients with CD was 112/100,000 person-years with an excess risk of 31/100,000. Risk estimates were highest in the first year after diagnosis (HR = 1.49; 95% CI = 0.83-2.67) and gradually decreased (>5 years after CD diagnosis, HR = 1.33; 95% CI = 1.00-1.79).
  
  
  CONCLUSIONS
  Endometriosis seems to be associated with prior CD. Potential explanations include shared etiological factors and CD-mediated inflammation.
authors.affiliation: Clinical Epidemiology Unit, Department of Medicine, Karolinska University Hospital and Karolinska Institutet, 171 76 Stockholm, Sweden.
authors.forename: Olof
authors.initials: O
authors.lastname: Stephansson
authors.forename: Henrik
authors.initials: H
authors.lastname: Falconer
authors.forename: Jonas F
authors.initials: JF
authors.lastname: Ludvigsson
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001706:Biopsy / Q000379:methods; D002446:Celiac Disease / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology; D015331:Cohort Studies; D004715:Endometriosis / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology; D005060:Europe; D005260:Female; D006801:Humans; D007246:Infertility / Q000175:diagnosis / Q000473:pathology; D007249:Inflammation; D008875:Middle Aged; D016016:Proportional Hazards Models; D012042:Registries; D012306:Risk; D013548:Sweden