title: Placental telomere length and risk of placental abruption.
abstract: OBJECTIVE
  To investigate the associations of placental telomere length with placental abruption (PA) risk and interactions between placental telomere length and placental mitochondrial DNA (mtDNA) copy number on PA risk.
  
  
  METHODS
  Relative telomere length and mtDNA copy number in placental samples collected from 105 cases and 73 controls were measured in two batches using qRT-PCR. Mean differences in relative telomere length between PA cases and controls were examined. After creating batch-specific median cutoffs for relative telomere length (84.92 and 102.53) and mtDNA copy number (2.32 and 1.42), interaction between the two variables was examined using stratified logistic regression models.
  
  
  RESULTS
  Adjusted mean difference in relative telomere length between PA cases and controls was -0.07 (p > 0.05). Among participants with low mtDNA copy number, participants with short relative telomere length had a 3.07-fold higher odds (95% CI: 1.13-8.38) of PA as compared with participants with long relative telomere length (the reference group). Among participants with high mtDNA copy number, participants with short relative telomere length had a 0.71-fold lower odds (95% CI: 0.28-1.83) of PA as compared with the reference group (interaction p values = 0.03).
  
  
  CONCLUSIONS
  Findings suggest complex relationships between placental telomere length, mtDNA copy number and PA risk which warrant further larger studies.
authors.affiliation: a Department of Epidemiology , School of Public Health, University of Washington , Seattle , WA , USA .
authors.forename: Tsegaselassie
authors.initials: T
authors.lastname: Workalemahu
authors.affiliation: a Department of Epidemiology , School of Public Health, University of Washington , Seattle , WA , USA .|b Center for Perinatal Studies, Swedish Medical Center , Seattle , WA , USA .
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Enquobahrie
authors.affiliation: a Department of Epidemiology , School of Public Health, University of Washington , Seattle , WA , USA .
authors.forename: Ermias
authors.initials: E
authors.lastname: Yohannes
authors.affiliation: c Peruana De Ciencias Aplicadas , Lima , Peru , and.
authors.forename: Sixto E
authors.initials: SE
authors.lastname: Sanchez
authors.affiliation: d Department of Epidemiology , Harvard T.H. Chan School of Public Health , Boston , MA , USA.
authors.forename: Bizu
authors.initials: B
authors.lastname: Gelaye
authors.affiliation: b Center for Perinatal Studies, Swedish Medical Center , Seattle , WA , USA .
authors.forename: Chunfang
authors.initials: C
authors.lastname: Qiu
authors.affiliation: d Department of Epidemiology , Harvard T.H. Chan School of Public Health , Boston , MA , USA.
authors.forename: Michelle A
authors.initials: MA
authors.lastname: Williams
mesh_terms: D000037:Abruptio Placentae / Q000209:etiology*; D000328:Adult; D016022:Case-Control Studies; D004272:DNA, Mitochondrial / Q000737:chemistry*; D005260:Female; D018628:Gene Dosage; D006801:Humans; D010920:Placenta / Q000737:chemistry; D011247:Pregnancy; D059505:Telomere Homeostasis; D055815:Young Adult
chemical_list: D004272:DNA, Mitochondrial
keywords: Oxidative stress; placental abruption; placental mtDNA copy number; placental telomere length; pregnancy