title: Perinatal mortality associated with abruptio placenta in singletons and multiples.
abstract: OBJECTIVE
  This study was undertaken to investigate the association among plurality (number of fetuses per pregnancy), abruptio placenta, and perinatal mortality.
  
  
  METHODS
  A retrospective cohort study on 15,051,872 singletons, 413,619 twins, and 22,585 triplets delivered in the United States between 1995 and 1998 was conducted. We compared the occurrence of perinatal death between pregnancies complicated by abruptio placenta and those without with the use of adjusted odds ratios. The generalized estimating equations framework was applied to adjust for intracluster correlations among multiples.
  
  
  RESULTS
  Placental abruption occurred among 93,968 singletons (6.2 per 1000), 5051 twin (12.2 per 1000), and 353 triplet (15.6 per 1000) gestations ( P for trend<.0001). Placental abruption was associated with significant risk of mortality irrespective of the plurality subtype. Perinatal mortality was greatest among singletons (adjusted odds ratio [95% CI]=14.3[13.2-15.4]), followed by twins (4.4[3.9-4.9]) and least among triplets (3.0[2.0-4.6]) ( P for trend<.0001).
  
  
  CONCLUSIONS
  As plurality increases from 1 to 3, the risk of placental abruption rises, whereas the risk of abruptio-associated perinatal mortality declines.
authors: Department of Maternal and Child Health, University of Alabama at Birmingham 35294, USA. hsalihu@uab.edu
authors: Hamisu M
authors: HM
authors: Salihu
authors: Brigitte
authors: B
authors: Bekan
authors: Muktar H
authors: MH
authors: Aliyu
authors: Dwight J
authors: DJ
authors: Rouse
authors: Russell S
authors: RS
authors: Kirby
authors: Greg R
authors: GR
authors: Alexander
mesh_terms: D000037:Abruptio Placentae / Q000453:epidemiology / Q000401:mortality*; D000328:Adult; D015331:Cohort Studies; D005260:Female; D006801:Humans; D015994:Incidence; D007226:Infant Mortality; D007231:Infant, Newborn; D016015:Logistic Models; D016017:Odds Ratio; D011247:Pregnancy; D011256:Pregnancy Outcome / Q000453:epidemiology; D011272:Pregnancy, Multiple; D012189:Retrospective Studies; D012307:Risk Factors; D014310:Triplets; D014427:Twins; D014481:United States / Q000453:epidemiology