title: Circulating Sex Hormones and Risk of Uterine Fibroids: Study of Women's Health Across the Nation (SWAN).
abstract: BACKGROUND
  Estrogen has been implicated in the development of uterine fibroids. However, the contribution of androgen in women is unknown.
  
  
  OBJECTIVE
  Our objective was to assess the longitudinal relations of circulating androgens and estradiol (E2) and their joint effects to the risk of developing fibroids.
  
  
  METHODS
  This is a 13-year longitudinal study in the Study of Women's Health Across the Nation.
  
  
  METHODS
  This study was conducted in seven sites across the United States (1997-2013).
  
  
  METHODS
  At baseline, 3240 pre- or early peri-menopausal women with an intact uterus, ages 45-52 years were included; 43.6% completed the follow-up. There were 512 incident and 478 recurrent fibroid cases.
  
  
  METHODS
  We measured near-annual time-varying serum levels of bioavailable E2 and bioavailable T, dichotomized at the median (high vs low).
  
  
  METHODS
  We estimated the conditional odds ratio (OR) of fibroids in the ensuing year using discrete-time proportional odds models adjusted for race/ethnicity/site, age, body mass index, menopausal stage, reproductive factors, smoking, timing of blood draw, and FSH.
  
  
  RESULTS
  Women with high T had a statistically significant increased risk of incident fibroids (OR, 1.33; 95% confidence interval [CI], 1.01-1.76; P = .04), but not recurrent fibroids. This risk was further elevated in those with high T and E2 (OR, 1.52; 95% CI, 1.07-2.17; P = .02). High E2 and T was associated with lower risk of recurrent fibroids (OR, 0.50; 95% CI, 0.26-0.96; P = .04).
  
  
  CONCLUSIONS
  High T with high E2 was associated with an elevated risk of incident fibroids in midlife women who never reported fibroids before baseline. Conversely, the risk of recurrent fibroids was mitigated in women with high E2 and high T.
authors.affiliation: Department of Medicine (J.Y.Y.W., J.S.L.), Division of Endocrinology, Gerontology, and Metabolism, and Department of Health Research and Policy, Division of Epidemiology, Stanford University School of Medicine, Stanford, California 94305; Department of Public Health Sciences (E.B.G.), Division of Epidemiology, University of California Davis School of Medicine, Davis, California 95616; Department of Statistics (W.O.J.), University of California Irvine, Irvine, California 92697; and Medical Services and Cooperative Studies Program Coordinating Center, Veterans Affairs Cooperative Studies Program (J.S.L.), Veterans Affairs Palo Alto Health Care System, Palo Alto, California 94304.
authors.forename: Jason Y Y
authors.initials: JY
authors.lastname: Wong
authors.affiliation: Department of Medicine (J.Y.Y.W., J.S.L.), Division of Endocrinology, Gerontology, and Metabolism, and Department of Health Research and Policy, Division of Epidemiology, Stanford University School of Medicine, Stanford, California 94305; Department of Public Health Sciences (E.B.G.), Division of Epidemiology, University of California Davis School of Medicine, Davis, California 95616; Department of Statistics (W.O.J.), University of California Irvine, Irvine, California 92697; and Medical Services and Cooperative Studies Program Coordinating Center, Veterans Affairs Cooperative Studies Program (J.S.L.), Veterans Affairs Palo Alto Health Care System, Palo Alto, California 94304.
authors.forename: Ellen B
authors.initials: EB
authors.lastname: Gold
authors.affiliation: Department of Medicine (J.Y.Y.W., J.S.L.), Division of Endocrinology, Gerontology, and Metabolism, and Department of Health Research and Policy, Division of Epidemiology, Stanford University School of Medicine, Stanford, California 94305; Department of Public Health Sciences (E.B.G.), Division of Epidemiology, University of California Davis School of Medicine, Davis, California 95616; Department of Statistics (W.O.J.), University of California Irvine, Irvine, California 92697; and Medical Services and Cooperative Studies Program Coordinating Center, Veterans Affairs Cooperative Studies Program (J.S.L.), Veterans Affairs Palo Alto Health Care System, Palo Alto, California 94304.
authors.forename: Wesley O
authors.initials: WO
authors.lastname: Johnson
authors.affiliation: Department of Medicine (J.Y.Y.W., J.S.L.), Division of Endocrinology, Gerontology, and Metabolism, and Department of Health Research and Policy, Division of Epidemiology, Stanford University School of Medicine, Stanford, California 94305; Department of Public Health Sciences (E.B.G.), Division of Epidemiology, University of California Davis School of Medicine, Davis, California 95616; Department of Statistics (W.O.J.), University of California Irvine, Irvine, California 92697; and Medical Services and Cooperative Studies Program Coordinating Center, Veterans Affairs Cooperative Studies Program (J.S.L.), Veterans Affairs Palo Alto Health Care System, Palo Alto, California 94304.
authors.forename: Jennifer S
authors.initials: JS
authors.lastname: Lee
mesh_terms: D000328:Adult; D000728:Androgens / Q000097:blood; D004958:Estradiol / Q000097:blood; D005260:Female; D005500:Follow-Up Studies; D012739:Gonadal Steroid Hormones / Q000097:blood*; D006306:Health Surveys; D006801:Humans; D007889:Leiomyoma / Q000097:blood* / Q000453:epidemiology*; D008137:Longitudinal Studies; D008875:Middle Aged; D012008:Recurrence; D018570:Risk Assessment; D012907:Smoking / Q000009:adverse effects / Q000453:epidemiology; D014481:United States / Q000453:epidemiology; D014930:Women; D016387:Women's Health
chemical_list: D000728:Androgens; D012739:Gonadal Steroid Hormones; D004958:Estradiol