title: Intrauterine devices and endometrial cancer risk: a pooled analysis of the Epidemiology of Endometrial Cancer Consortium.
abstract: Intrauterine devices (IUDs), long-acting and reversible contraceptives, induce a number of immunological and biochemical changes in the uterine environment that could affect endometrial cancer (EC) risk. We addressed this relationship through a pooled analysis of data collected in the Epidemiology of Endometrial Cancer Consortium. We combined individual-level data from 4 cohort and 14 case-control studies, in total 8,801 EC cases and 15,357 controls. Using multivariable logistic regression, we estimated pooled odds ratios (pooled-ORs) and 95% confidence intervals (CIs) for EC risk associated with ever use, type of device, ages at first and last use, duration of use and time since last use, stratified by study and adjusted for confounders. Ever use of IUDs was inversely related to EC risk (pooled-OR = 0.81, 95% CI = 0.74-0.90). Compared with never use, reduced risk of EC was observed for inert IUDs (pooled-OR = 0.69, 95% CI = 0.58-0.82), older age at first use (≥ 35 years pooled-OR = 0.53, 95% CI = 0.43-0.67), older age at last use (≥ 45 years pooled-OR = 0.60, 95% CI = 0.50-0.72), longer duration of use (≥ 10 years pooled-OR = 0.61, 95% CI = 0.52-0.71) and recent use (within 1 year of study entry pooled-OR = 0.39, 95% CI = 0.30-0.49). Future studies are needed to assess the respective roles of detection biases and biologic effects related to foreign body responses in the endometrium, heavier bleeding (and increased clearance of carcinogenic cells) and localized hormonal changes.
authors.affiliation: Hormonal and Reproductive Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD; Cancer Prevention Fellowship Program, Division of Cancer Prevention, National Cancer Institute, Bethesda, MD.
authors.forename: Ashley S
authors.initials: AS
authors.lastname: Felix
authors.forename: Mia M
authors.initials: MM
authors.lastname: Gaudet
authors.forename: Carlo
authors.initials: C
authors.lastname: La Vecchia
authors.forename: Christina M
authors.initials: CM
authors.lastname: Nagle
authors.forename: Xiao Ou
authors.initials: XO
authors.lastname: Shu
authors.forename: Elisabete
authors.initials: E
authors.lastname: Weiderpass
authors.forename: Hans Olov
authors.initials: HO
authors.lastname: Adami
authors.forename: Shirley
authors.initials: S
authors.lastname: Beresford
authors.forename: Leslie
authors.initials: L
authors.lastname: Bernstein
authors.forename: Chu
authors.initials: C
authors.lastname: Chen
authors.forename: Linda S
authors.initials: LS
authors.lastname: Cook
authors.forename: Immaculata
authors.initials: I
authors.lastname: De Vivo
authors.forename: Jennifer A
authors.initials: JA
authors.lastname: Doherty
authors.forename: Christine M
authors.initials: CM
authors.lastname: Friedenreich
authors.forename: Susan M
authors.initials: SM
authors.lastname: Gapstur
authors.forename: Dierdre
authors.initials: D
authors.lastname: Hill
authors.forename: Pamela L
authors.initials: PL
authors.lastname: Horn-Ross
authors.forename: James V
authors.initials: JV
authors.lastname: Lacey
authors.forename: Fabio
authors.initials: F
authors.lastname: Levi
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Liang
authors.forename: Lingeng
authors.initials: L
authors.lastname: Lu
authors.forename: Anthony
authors.initials: A
authors.lastname: Magliocco
authors.forename: Susan E
authors.initials: SE
authors.lastname: McCann
authors.forename: Eva
authors.initials: E
authors.lastname: Negri
authors.forename: Sara H
authors.initials: SH
authors.lastname: Olson
authors.forename: Julie R
authors.initials: JR
authors.lastname: Palmer
authors.forename: Alpa V
authors.initials: AV
authors.lastname: Patel
authors.forename: Stacey
authors.initials: S
authors.lastname: Petruzella
authors.forename: Jennifer
authors.initials: J
authors.lastname: Prescott
authors.forename: Harvey A
authors.initials: HA
authors.lastname: Risch
authors.forename: Lynn
authors.initials: L
authors.lastname: Rosenberg
authors.forename: Mark E
authors.initials: ME
authors.lastname: Sherman
authors.forename: Amanda B
authors.initials: AB
authors.lastname: Spurdle
authors.forename: Penelope M
authors.initials: PM
authors.lastname: Webb
authors.forename: Lauren A
authors.initials: LA
authors.lastname: Wise
authors.forename: Yong-Bing
authors.initials: YB
authors.lastname: Xiang
authors.forename: Wanghong
authors.initials: W
authors.lastname: Xu
authors.forename: Hannah P
authors.initials: HP
authors.lastname: Yang
authors.forename: Herbert
authors.initials: H
authors.lastname: Yu
authors.forename: Anne
authors.initials: A
authors.lastname: Zeleniuch-Jacquotte
authors.forename: Louise A
authors.initials: LA
authors.lastname: Brinton
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D015331:Cohort Studies; D003267:Contraception; D016889:Endometrial Neoplasms / Q000453:epidemiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007434:Intrauterine Devices / Q000009:adverse effects* / Q000706:statistics & numerical data; D015201:Meta-Analysis as Topic; D008875:Middle Aged; D011379:Prognosis; D012307:Risk Factors; D014481:United States / Q000453:epidemiology
keywords: contraception; endometrial neoplasm; etiology; pooled analysis