title: Trends, risk factors and mortality among women with venous thromboembolism during labour and delivery: a population-based study of 8 million births.
abstract: OBJECTIVE
  Venous thromboembolism (VTE) is amongst the main causes of maternal death in the developed world. The objective of this study is to elucidate risk factors of VTE and specifically, predictors of fatal thromboembolic disease during the delivery.
  
  
  METHODS
  We conducted a population-based cohort study on 8 million birth records using the Healthcare Cost and Utilisation Project-Nationwide Inpatient Sample from 1999 to 2008 to estimate the incidence and case fatality of VTE's during labour admission. Logistic regression was used to calculate the odds ratio (OR) and corresponding 95 % confidence intervals (CIs) of demographic and obstetrical determinants of VTEs and fatal VTEs.
  
  
  RESULTS
  The overall incidence of VTE was 167.7/100,000 births, increasing over the 10-year period, with an average case fatality rate of 0.41 %. VTE was associated with maternal age above 25, elderly primigravida, multigravida, black race, smoking, thrombophilia, cardiovascular disease, hypertension, obesity, postpartum haemorrhage and blood transfusion. Predictors of VTE fatalities included black race, hypertension, caesarean section and transfusion.
  
  
  CONCLUSIONS
  VTE is a rare but serious condition that is increasing in incidence and is associated with a significant degree of maternal morbidity and mortality. Further research targeting prevention among high-risk groups is warranted.
authors.affiliation: Department of Obstetrics and Gynecology, Jewish General Hospital, 5790 Cote-Des-Neiges Road, Pav H, Room 325, Montreal, QC, H3S 1Y9, Canada.
authors.forename: Nimrah
authors.initials: N
authors.lastname: Abbasi
authors.forename: Jacques
authors.initials: J
authors.lastname: Balayla
authors.forename: Denny P
authors.initials: DP
authors.lastname: Laporta
authors.forename: Abbas
authors.initials: A
authors.lastname: Kezouh
authors.forename: Haim A
authors.initials: HA
authors.lastname: Abenhaim
mesh_terms: D000328:Adult; D015331:Cohort Studies; D036861:Delivery, Obstetric / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D015994:Incidence; D007743:Labor, Obstetric; D008428:Maternal Mortality; D007744:Obstetric Labor Complications / Q000209:etiology / Q000401:mortality*; D011247:Pregnancy; D011250:Pregnancy Complications, Hematologic / Q000209:etiology / Q000401:mortality*; D018566:Pregnancy, High-Risk; D012307:Risk Factors; D014481:United States / Q000453:epidemiology; D054556:Venous Thromboembolism / Q000209:etiology / Q000401:mortality*