title: Pregnancy outcome of patients following deep venous thrombosis.
abstract: OBJECTIVE
  To investigate pregnancy outcome of patients with a history of deep vein thrombosis (DVT).
  
  
  METHODS
  A population-based study comparing all pregnancies of patients with and without a history of DVT was conducted. Deliveries occurred during the years 1988-2007 at a tertiary Medical Center. Stratified analyses were performed using multivariable logistic regression models and the Mantel-Haenszel technique.
  
  
  RESULTS
  During the study there were 212,086 deliveries, of which 122 (0.06%) occurred in patients with a history of DVT. Using a multivariate analysis, with backward elimination, the following conditions were significantly associated with DVT: advanced maternal age (OR, 1.1; 95% CI, 1.02-1.1; p = 0.004), chronic hypertension (OR, 2.9; 95% CI, 1.4-6.0; p = 0.005) and previous caesarean delivery (OR, 2.8; 95% CI, 1.9-4.1; p < 0.001). Patients with a history of DVT were more likely to have caesarean deliveries (OR, 2.6; 95% CI, 1.8-3.8; p < 0.001) than non-DVT patients. After controlling for possible confounders, such as maternal age, hypertensive disorders, pregestational diabetes and multiple gestations, by using another multivariate analysis with preterm delivery (<37 weeks' gestation) as the outcome variable, DVT was found to be an independent risk factor for preterm birth (OR, 1.8; 95% CI, 1.1-2.9; p = 0.033). This association remained significant after controlling for labor induction, using the Mantel-Haenszel technique (OR, 1.8; 95% CI, 1.1-3.0; p = 0.011). No significant differences were noted between the groups regarding perinatal outcomes such as low Apgar scores, congenital malformations or perinatal mortality.
  
  
  CONCLUSIONS
  A history of DVT is an independent risk factor for spontaneous preterm delivery. Nevertheless, in our population it is not associated with adverse perinatal outcome.
authors.affiliation: Department of Obstetrics and Gynecology, Soroka University Medical Center, Ben Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Ronen
authors.initials: R
authors.lastname: Ben-Joseph
authors.forename: Amalia
authors.initials: A
authors.lastname: Levy
authors.forename: Arnon
authors.initials: A
authors.lastname: Wiznitzer
authors.forename: Gershon
authors.initials: G
authors.lastname: Holcberg
authors.forename: Moshe
authors.initials: M
authors.lastname: Mazor
authors.forename: Eyal
authors.initials: E
authors.lastname: Sheiner
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D007557:Israel / Q000453:epidemiology; D016015:Logistic Models; D011247:Pregnancy; D011248:Pregnancy Complications / Q000209:etiology*; D011256:Pregnancy Outcome; D020246:Venous Thrombosis / Q000150:complications*; D055815:Young Adult