title: Stillbirth risk in a second pregnancy.
abstract: OBJECTIVE
  To estimate the risk of stillbirth in a second pregnancy when previous stillbirth, preterm, and small-for-gestational age (SGA) births occurred in the previous pregnancy.
  
  
  METHODS
  This was a population-based cohort study in New South Wales Australia from 2002 to 2006. Singleton births in a first pregnancy were linked to a second pregnancy using data from the New South Wales Midwives Data Collection and the New South Wales Perinatal Death Database. Deaths were classified according to the Perinatal Mortality Classifications of the Perinatal Society of Australia and New Zealand. Crude and adjusted hazard ratios were estimated using a proportional hazards model.
  
  
  RESULTS
  Delivery of an SGA newborn in the first pregnancy was associated with increased risks of stillbirth in a second pregnancy (hazard ratio 1.73, 95% confidence interval [CI] 1.15-2.60) and risk was further increased with prematurity (hazard ratio 5.65, 95% CI 1.76-18.12). Stillbirth in a first pregnancy had a nonsignificant association with stillbirth in the second pregnancy (hazard ratio 2.03, 95% CI 0.60-6.90). For women aged 30-34 years, the absolute risk of stillbirth up to 40 completed weeks of gestation was 4.84 per 1,000 among women whose first pregnancy was a stillbirth and 7.19 per 1,000 among women whose first pregnancy was preterm and SGA.
  
  
  CONCLUSIONS
  Delivering an SGA and preterm neonate in a first pregnancy is associated with greater risks for stillbirth in a second pregnancy than delivering a previous stillbirth. All factors merit improved surveillance in a subsequent pregnancy, and research should address underlying factors common to all three outcomes.
authors.affiliation: Department of Neonatal Medicine, Royal Prince Alfred Hospital, Sydney School of Public Health and Sydney Medical School, University of Sydney, New South Wales, Australia. adrienne.gordon@email.cs.nsw.gov.au
authors.forename: Adrienne
authors.initials: A
authors.lastname: Gordon
authors.forename: Camille
authors.initials: C
authors.lastname: Raynes-Greenow
authors.forename: Kevin
authors.initials: K
authors.lastname: McGeechan
authors.forename: Jonathan
authors.initials: J
authors.lastname: Morris
authors.forename: Heather
authors.initials: H
authors.lastname: Jeffery
mesh_terms: D000328:Adult; D015331:Cohort Studies; D015897:Comorbidity; D003920:Diabetes Mellitus / Q000453:epidemiology; D016640:Diabetes, Gestational / Q000453:epidemiology; D005260:Female; D006801:Humans; D006973:Hypertension / Q000453:epidemiology; D007231:Infant, Newborn; D007234:Infant, Premature; D007236:Infant, Small for Gestational Age; D009517:New South Wales / Q000453:epidemiology; D011225:Pre-Eclampsia / Q000453:epidemiology; D011247:Pregnancy; D012306:Risk; D012907:Smoking / Q000453:epidemiology; D050497:Stillbirth / Q000453:epidemiology*; D055815:Young Adult