title: A case-control study of unexplained antepartum stillbirths.
abstract: OBJECTIVE
  To ascertain factors that will identify women who are at increased risk of unexplained antepartum stillbirth.
  
  
  METHODS
  Matched case-control study. The cases and controls were initially analysed as a whole group and again after dichotomizing into those of low birthweight (< 2500 g) and those of normal birthweight (> or = 2500 g).
  
  
  METHODS
  Western Australia 1980-1983.
  
  
  METHODS
  Unexplained antepartum stillbirths of > or = 1000 g birthweight (cases) and liveborn infants individually matched for year of birth, plurality, sex and birthweight of infant and race of mother (controls).
  
  
  RESULTS
  The case pregnancies had more polyhydramnios (OR 10.83, 95% CI 2.41-48.69) and cord problems (OR 6.57 95% CI 1.36-31.75) than the controls but, paradoxically, other obstetric and medical complications were less common in the cases. The association with polyhydramnios persisted when the analysis was confined to those with low birthweight. With normal birthweight fetal distress was more frequent in the cases (OR 3.65 95% CI 1.36-9.80) but there were few other differences.
  
  
  CONCLUSIONS
  The clinical and diagnostic systems currently in use are unable to identify many fetuses at risk of death. Decreases in the rate of unexplained antepartum stillbirths await the discovery of new preventable causes, or of innovations in clinical or laboratory aspects of obstetric care.
authors.affiliation: Western Australian Research Institute for Child Health, Perth.
authors.forename: L M
authors.initials: LM
authors.lastname: Alessandri
authors.forename: F J
authors.initials: FJ
authors.lastname: Stanley
authors.forename: J B
authors.initials: JB
authors.lastname: Garner
authors.forename: J
authors.initials: J
authors.lastname: Newnham
authors.forename: B N
authors.initials: BN
authors.lastname: Walters
mesh_terms: D001724:Birth Weight; D001794:Blood Pressure / Q000502:physiology; D016022:Case-Control Studies; D005260:Female; D005313:Fetal Death / Q000453:epidemiology / Q000209:etiology*; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D006831:Polyhydramnios / Q000150:complications; D011247:Pregnancy; D012307:Risk Factors; D014470:Umbilical Cord; D015430:Weight Gain