title: Fetal death and placental weight/birthweight ratio: a population study.
abstract: OBJECTIVE
  To study the association of placental weight and placental weight/birthweight ratio with gestational age-specific fetal death.
  
  
  METHODS
  Population-based study.
  
  
  METHODS
  Medical Birth Registry of Norway.
  
  
  METHODS
  All singleton births in Norway, 1999-2008 (n = 534 892).
  
  
  METHODS
  Gestational age-specific quartiles of placental weight and placental weight/birthweight ratio were estimated, and proportions of fetal deaths and live births within the lowest and highest quartile were compared. The risk of fetal death associated with placental weight/birthweight ratio was estimated as crude and adjusted odds ratios.
  
  
  METHODS
  Offspring vital status.
  
  
  RESULTS
  Pregnancies with fetal death were overrepresented in the lowest quartile of placental weight and placental weight/birthweight ratio in term and preterm deliveries. In preterm deliveries, fetal deaths were also overrepresented in the highest placental weight/birthweight ratio. Adjusted odds ratio of fetal death in preterm deliveries was 1.67 (95% confidence interval 1.44-1.94) for placental weight/birthweight ratio in the lowest quartile and 1.79 (95% confidence interval 1.55-2.08) in the highest quartile. Corresponding odds ratios for deliveries at term were 1.76 (95% confidence interval 1.50-2.06) and 1.18 (95% confidence interval 0.99-1.41).
  
  
  CONCLUSIONS
  Both small and large placentas relative to birthweight were associated with fetal death in preterm births. At term, only small placentas relative to birthweight were associated with fetal death. Understanding the mechanisms behind the increased risk of adverse pregnancy outcomes in pregnancies with disproportionate placental weight/birthweight ratio may be important for prevention of fetal deaths.
authors: Department of Gynecology and Obstetrics, Akershus University Hospital and Institute of Clinical Medicine, University of Oslo, Lørenskog, Norway. marit.camilla.haavaldsen@ahus.no
authors: Camilla
authors: C
authors: Haavaldsen
authors: Sven O
authors: SO
authors: Samuelsen
authors: Anne
authors: A
authors: Eskild
mesh_terms: D001724:Birth Weight; D005260:Female; D005313:Fetal Death / Q000453:epidemiology* / Q000473:pathology; D005865:Gestational Age; D006801:Humans; D050498:Live Birth / Q000453:epidemiology; D009664:Norway / Q000453:epidemiology; D016017:Odds Ratio; D009929:Organ Size; D010920:Placenta / Q000473:pathology*; D011247:Pregnancy; D012042:Registries; D050497:Stillbirth / Q000453:epidemiology