title: Oestradiol levels may differ between premenopausal women, ages 18-50, with type 1 diabetes and matched controls.
abstract: This study aimed to investigate whether oestradiol differs between premenopausal women with and without type 1 diabetes and whether levels are associated with such factors as age, reproductive history or diabetes management.
  
  
  
  Oestradiol in premenopausal women with type 1 diabetes (n = 89; age = 18-50 years; duration = 13-18 years) and age-matched/race-matched controls without diabetes (n = 76) was collected during a cross-sectional ancillary study of the Wisconsin Diabetes Registry Study, a population-based incident cohort. Total and bioavailable oestradiol and sex hormone-binding globulin were compared using multivariable regression (e.g. adjusting for reproductive history).
  
  
  
  Adjusted mean total and bioavailable oestradiol did not differ overall by diabetes status (p ≥ 0.74), while adjusted mean sex hormone-binding globulin was higher in type 1 diabetes women (p = 0.02). However, only in women with type 1 diabetes and not controls (interaction p = 0.0005) was total oestradiol positively associated with the duration of reproductive years with unsuppressed ovarian function (UnsuppOvFx = years since menarche minus years on hormonal contraceptives/pregnant/breastfeeding). When stratified into less than/equal to or greater than the median 9 years' duration of UnsuppOvFx, compared with controls, women with type 1 diabetes had significantly lower total oestradiol in the ≤9 years group [β = -43.2 pg mL-1(-158.6 pmol L-1), p = 0.04] and significantly higher total oestradiol in the >9 years group [β = 53.9 pg mL-1(197.9 pmol L-1), p = 0.04]. Results remained consistent during additional statistical adjustments and sensitivity analyses.
  
  
  
  Compared with controls, women with type 1 diabetes may have lower oestradiol when they have a shorter duration of UnsuppOvFx and higher oestradiol when they have a longer duration of UnsuppOvFx. Given the potential effects of insulin on ovarian function, oestradiol production may vary across the lifespan for women with type 1 diabetes. Copyright © 2016 John Wiley & Sons, Ltd.
authors.affiliation: Division of Epidemiology and Biostatistics, University of Illinois at Chicago, Chicago, IL, USA.
authors.forename: Lina Saleh
authors.initials: LS
authors.lastname: Hassan
authors.affiliation: Division of Transplant Surgery, University of Illinois at Chicago, Chicago, IL, USA.
authors.forename: Rebecca S
authors.initials: RS
authors.lastname: Monson
authors.affiliation: Division of Epidemiology and Biostatistics, University of Illinois at Chicago, Chicago, IL, USA.|Division of Transplant Surgery, University of Illinois at Chicago, Chicago, IL, USA.
authors.forename: Kirstie K
authors.identifier: 0000-0002-9077-2092
authors.initials: KK
authors.lastname: Danielson
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D003922:Diabetes Mellitus, Type 1 / Q000503:physiopathology* / Q000628:therapy; D019468:Disease Management; D004958:Estradiol / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D017697:Premenopause; D011379:Prognosis; D012098:Reproduction; D055815:Young Adult
chemical_list: D004958:Estradiol
keywords: SHBG; oestradiol; ovarian function; premenopausal; type 1 diabetes