title: A prospective cohort study comparing the reactogenicity of trivalent influenza vaccine in pregnant and non-pregnant women.
abstract: BACKGROUND
  Influenza vaccination during pregnancy can prevent serious illness in expectant mothers and provide protection to newborns; however, historically uptake has been limited due to a number of factors, including safety concerns. Symptomatic complaints are common during pregnancy and may be mistakenly associated with reactions to trivalent influenza vaccine (TIV). To investigate this, we compared post-vaccination events self-reported by pregnant women to events reported by non-pregnant women receiving TIV.
  
  
  METHODS
  A prospective cohort of 1,086 pregnant women and 314 non-pregnant female healthcare workers (HCWs) who received TIV between March-May 2014 were followed-up seven days post-vaccination to assess local and systemic adverse events following immunisation (AEFIs). Women were surveyed by text message regarding perceived reactions to TIV. Those reporting an AEFI completed an interview by telephone or mobile phone to ascertain details. Logistic regression models adjusting for age and residence were used to compare reactions reported by pregnant women and non-pregnant HCWs.
  
  
  RESULTS
  Similar proportions of pregnant women and non-pregnant, female HCWs reported ≥1 reaction following vaccination with TIV (13.0% and 17.3%, respectively; OR = 1.2 [95% CI: 0.8-1.8]). Non-pregnant, female HCWs were more likely to report fever or headache compared to pregnant women (OR: 4.6 [95% CI 2.1-10.3] and OR: 2.2 [95% CI 1.0-4.6], respectively). No other significant differences in reported symptoms were observed. No serious vaccine-associated adverse events were reported, and less than 2% of each group sought medical advice for a reaction.
  
  
  CONCLUSIONS
  We found no evidence suggesting pregnant women are more likely to report adverse events following influenza vaccination when compared to non-pregnant female HCWs of similar age, and in some cases, pregnant women reported significantly fewer adverse events. These results further support the safety of TIV administered in pregnant women.
authors.affiliation: School or Pathology and Laboratory Medicine, University of Western Australia, 227 Stubbs Terrace Shenton Park, Western Australia, Australia. Annette.Regan@health.wa.gov.au.|Communicable Disease Control Directorate, Western Australia Department of Health, Shenton Park, Western Australia, Australia. Annette.Regan@health.wa.gov.au.
authors.forename: Annette K
authors.initials: AK
authors.lastname: Regan
authors.affiliation: Communicable Disease Control Directorate, Western Australia Department of Health, Shenton Park, Western Australia, Australia. Lauren.Tracey@health.wa.gov.au.
authors.forename: Lauren
authors.initials: L
authors.lastname: Tracey
authors.affiliation: School of Paediatrics and Child Health, University of Western Australia, Crawley, Western Australia, Australia. Christopher.Blyth@uwa.edu.au.|Vaccine Trials Group, Telethon Kids Institute, University of Western Australia, Subiaco, Western Australia, Australia. Christopher.Blyth@uwa.edu.au.
authors.forename: Christopher C
authors.initials: CC
authors.lastname: Blyth
authors.affiliation: Communicable Disease Control Directorate, Western Australia Department of Health, Shenton Park, Western Australia, Australia. Donna.Mak@health.wa.gov.au.
authors.forename: Donna B
authors.initials: DB
authors.lastname: Mak
authors.affiliation: School of Paediatrics and Child Health, University of Western Australia, Crawley, Western Australia, Australia. Peter.Richmond@uwa.edu.au.|Vaccine Trials Group, Telethon Kids Institute, University of Western Australia, Subiaco, Western Australia, Australia. Peter.Richmond@uwa.edu.au.
authors.forename: Peter C
authors.initials: PC
authors.lastname: Richmond
authors.affiliation: School or Pathology and Laboratory Medicine, University of Western Australia, 227 Stubbs Terrace Shenton Park, Western Australia, Australia. Geoff.Shellam@uwa.edu.au.
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Shellam
authors.affiliation: Vaccine Trials Group, Telethon Kids Institute, University of Western Australia, Subiaco, Western Australia, Australia. Caroline.Talbot@telethonkids.org.au.
authors.forename: Caroline
authors.initials: C
authors.lastname: Talbot
authors.affiliation: School or Pathology and Laboratory Medicine, University of Western Australia, 227 Stubbs Terrace Shenton Park, Western Australia, Australia. Paul.Effler@health.wa.gov.au.|Communicable Disease Control Directorate, Western Australia Department of Health, Shenton Park, Western Australia, Australia. Paul.Effler@health.wa.gov.au.
authors.forename: Paul V
authors.initials: PV
authors.lastname: Effler
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D015331:Cohort Studies; D005260:Female; D005334:Fever / Q000139:chemically induced*; D006261:Headache / Q000139:chemically induced*; D006801:Humans; D007252:Influenza Vaccines / Q000009:adverse effects*; D007251:Influenza, Human / Q000517:prevention & control*; D016015:Logistic Models; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000517:prevention & control*; D011446:Prospective Studies; D011795:Surveys and Questionnaires; D060145:Text Messaging
chemical_list: D007252:Influenza Vaccines