Maternal influenza immunization and adverse birth outcomes: Using data and practice to inform theory and research design

Varun K. Phadke, Mark C. Steinhoff, Saad B. Omer, Noni E. MacDonald

Research output: Contribution to journalReview articlepeer-review

5 Scopus citations


Maternal influenza immunization can reduce influenza-attributable morbidity and mortality among pregnant women and infants who are too young to be vaccinated. Data from empirical studies also support the hypothesis that immunization can protect the fetus against adverse outcomes if the mother is exposed to influenza. In their theoretical analysis in the Journal, Hutcheon et al. (Am J Epidemiol. 2016;184(3):227-232) critiqued the existing evidence of the fetal benefits of maternal influenza immunization by calculating the sample sizes needed to demonstrate hypothetical reductions in risk and concluded that the benefits observed in empirical studies are likely implausible. However, in their analysis, they did not take into account multiple fundamental characteristics of influenza epidemiology, including the time-variable effects of influenza illness and vaccination during pregnancy, or well-known differences in disease epidemiology between seasons, populations, and geographic regions. Although these and other factors might affect the magnitude of fetal benefit conferred by maternal influenza immunization, studies in which investigators have accounted for influenza circulation have demonstrated a consistent protective effect against a variety of adverse birth outcomes; those studies include the only randomized controlled trial designed a priori and adequately powered to do so. Only a comprehensive and nuanced assessment of the evidence base will allow for effective translation of these data into a global immunization policy.

Original languageEnglish (US)
Pages (from-to)789-792
Number of pages4
JournalAmerican journal of epidemiology
Issue number11
StatePublished - Dec 1 2016


  • Birth outcome
  • Birthweight
  • Influenza
  • Maternal immunization
  • Pregnancy
  • Preterm birth

ASJC Scopus subject areas

  • General Medicine


Dive into the research topics of 'Maternal influenza immunization and adverse birth outcomes: Using data and practice to inform theory and research design'. Together they form a unique fingerprint.

Cite this