title: Pulmonary embolism and stroke in relation to pregnancy: how can high-risk women be identified?
abstract: OBJECTIVE
  Risks of circulatory diseases are increased substantially during late pregnancy and around the time of delivery. This study was undertaken to determine whether preeclampsia, multiple pregnancy, or cesarean delivery account for the majority of pregnancy-related risks of pulmonary embolism and stroke (caused by hemorrhage, infarction, and intracranial venous thrombosis).
  
  
  METHODS
  We analyzed a population-based cohort of 1,003,489 deliveries in Sweden. Relative risks of pulmonary embolism and stroke were modeled by use of Poisson regression.
  
  
  RESULTS
  Preeclampsia was associated with 3- to 12-fold increases in risks of pulmonary embolism and stroke during late pregnancy, at delivery, and in the puerperium, and similar increases in risks were also observed for multiple pregnancies and cesarean delivery. These strong associations could not explain the overall pregnancy-related risks of pulmonary embolism and stroke.
  
  
  CONCLUSIONS
  Preeclampsia, multiple birth, and cesarean delivery are important risk factors for pulmonary embolism and stroke, but they do not account for the majority of the excess risks associated with pregnancy.
authors.affiliation: Department of Medical Epidemiology, Karolinska Institutet, Stockholm, Sweden. Helena.Ros@mep.ki.se
authors.forename: Helena Salonen
authors.initials: HS
authors.lastname: Ros
authors.forename: Paul
authors.initials: P
authors.lastname: Lichtenstein
authors.forename: Rino
authors.initials: R
authors.lastname: Bellocco
authors.forename: Gunnar
authors.initials: G
authors.lastname: Petersson
authors.forename: Sven
authors.initials: S
authors.lastname: Cnattingius
mesh_terms: D000328:Adult; D002585:Cesarean Section / Q000706:statistics & numerical data; D015331:Cohort Studies; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D011225:Pre-Eclampsia / Q000453:epidemiology; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology*; D011272:Pregnancy, Multiple / Q000706:statistics & numerical data; D011644:Puerperal Disorders / Q000453:epidemiology; D011655:Pulmonary Embolism / Q000453:epidemiology*; D012044:Regression Analysis; D018570:Risk Assessment / Q000379:methods; D020521:Stroke / Q000453:epidemiology*