title: Association of influenza vaccination on decreased stillbirth rate.
abstract: OBJECTIVE
  We have previously shown a decrease in the overall stillbirth rate at our institution in women receiving the seasonal influenza vaccine during pregnancy. The goal of this study was to ascertain factors associated with this decrease.
  
  
  METHODS
  This was a retrospective cohort study examining the stillbirth rate, etiology, autopsy findings, and placental pathology in pregnant women receiving the seasonal trivalent inactive influenza vaccine during five influenza seasons between 2003 and 2008. All stillbirths at our institution are investigated by a committee and an etiology is assigned. Autopsy is offered to all patients and placental evaluation is performed routinely.
  
  
  RESULTS
  During the study period, 8,690 pregnant women received the seasonal influenza vaccine antepartum and delivered at our institution. Thirty of these births were complicated by stillbirth as compared with 436 stillbirths in the 76,153 women not vaccinated (0.35 vs. 0.57%, p = 0.006). No association was identified between assigned causes of stillbirth when comparing vaccinated and nonvaccinated women.
  
  
  CONCLUSIONS
  No specific etiology commonly associated with stillbirth was identified to have been affected by maternal antepartum influenza vaccination.
authors.affiliation: Department of Obstetrics and Gynecology, The University of Texas Southwestern Medical Center, Dallas, Texas.
authors.forename: Alison C
authors.initials: AC
authors.lastname: Wortman
authors.affiliation: Department of Obstetrics and Gynecology, The University of Texas Southwestern Medical Center, Dallas, Texas.
authors.forename: Brian M
authors.initials: BM
authors.lastname: Casey
authors.affiliation: Department of Obstetrics and Gynecology, The University of Texas Southwestern Medical Center, Dallas, Texas.
authors.forename: Donald D
authors.initials: DD
authors.lastname: McIntire
authors.affiliation: Department of Obstetrics and Gynecology, The University of Texas Southwestern Medical Center, Dallas, Texas.
authors.forename: Jeanne S
authors.initials: JS
authors.lastname: Sheffield
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D007252:Influenza Vaccines / Q000008:administration & dosage*; D007251:Influenza, Human / Q000517:prevention & control*; D016015:Logistic Models; D010920:Placenta / Q000473:pathology*; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000517:prevention & control*; D012189:Retrospective Studies; D050497:Stillbirth / Q000453:epidemiology*; D014611:Vaccination / Q000706:statistics & numerical data*; D055815:Young Adult
chemical_list: D007252:Influenza Vaccines