title: Unexplained antepartum fetal deaths: what are the determinants?
abstract: OBJECTIVE
  The objective was to assess fetal, antenatal, and pregnancy determinants of unexplained antepartum fetal death.
  
  
  METHODS
  This is a hospital-based cohort study of 34,394 births weighing 500 g or more from January 1995 to December 2002. Unexplained fetal deaths were defined as fetal deaths occurring before labor, without evidence of significant fetal, maternal or placental pathology.
  
  
  RESULTS
  Ninety-eight unexplained antepartum fetal deaths accounted for 27.2% of 360 total fetal deaths. Two-thirds of these deaths occurred after 36 weeks' gestation. The following factors are independently associated with unexplained fetal deaths: primiparity (OR 1.74; 95% CI 1.21, 2.86); parity of five or more (OR 1.19; 95% CI 1.26, 3.26); low socioeconomic status (OR 1.22; 95% CI 1.14, 2.86); maternal age 40 years or more (OR 3.62; 95% CI 1.22, 4.52); maternal age of 18 years or less (OR 1.79; 95% CI 0.82, 2.89); maternal prepregnancy weight greater than 70 kg (OR 2.20; 95% CI 1.85, 3.68); fewer than three antenatal visits in women whose fetuses died at 31 weeks or more (OR 1.11; 95% CI 1.08, 2.48); birth weight ratio (defined as ratio of birth weight to mean birth weight for gestational age) between 0.85 and 0.94 (OR 1.77; 95% CI 1.28, 4.18) or over 1.45 (OR 2.92; 95% CI 1.75, 3.21); trimester of first antenatal visit. Previous fetal death, previous abortion, cigarette smoking, fetal sex, low maternal weight, fetal-to-placenta weight, and post date pregnancy were not significantly associated with unexplained fetal deaths.
  
  
  CONCLUSIONS
  Several factors were identified that are associated with an increased risk of unexplained fetal deaths.
authors.affiliation: Department of Obstetrics and Gynecology, King Faisal University Teaching Hospital, PO BOX 40126, 31952 Al Khobar, Kingdom of Saudi Arabia. rchibber57@hotmail.com
authors.forename: Rachana
authors.initials: R
authors.lastname: Chibber
mesh_terms: D001724:Birth Weight; D016009:Chi-Square Distribution; D015331:Cohort Studies; D005260:Female; D005313:Fetal Death / Q000453:epidemiology* / Q000209:etiology*; D046689:Fetal Mortality; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D008423:Maternal Age; D009765:Obesity; D010298:Parity; D011247:Pregnancy; D011248:Pregnancy Complications; D018566:Pregnancy, High-Risk; D011295:Prenatal Care / Q000706:statistics & numerical data; D012307:Risk Factors; D012529:Saudi Arabia / Q000453:epidemiology; D012923:Social Class