83. Maternal Characteristics Modify the Effect of Maternal Influenza Vaccination on Fetal Outcomes
Session: Oral Abstract Session: Influenza Vaccine - Clinical Impact and Vaccine Response
Thursday, October 3, 2013: 9:30 AM
Room: The Moscone Center: 200-212
Background:  Maternal infections during pregnancy have been associated with adverse fetal and infant health outcomes, and vaccination against influenza is the most effective tool to prevent morbidity and mortality due to seasonal and pandemic influenza. We evaluated the association between receipt of the inactivated seasonal influenza vaccine on preterm and small for gestational age (SGA) births with the aim to assess racial and socioeconomic variations in vaccine effect.

Methods: In this cohort study we used data from the Georgia pregnancy risk assessment and monitoring system, hospital discharge data and birth certificate data for the most recent four years available at the beginning of the study, a total of 8,393 live births in Georgia from January 1, 2005 through December 31, 2008.

Results:  Among all women, we found significant strong associations between maternal influenza vaccination and reduced odds of a preterm birth during the widespread influenza activity period [OR= 0.39, 95% CI: 0.18, 0.83]. In stratified models, vaccination was protective against SGA birth among women at higher risk for influenza related morbidity (i.e. women enrolled in the Women, Infant and Child (WIC) program [OR = 0.20, 95% CI: 0.04, 0.98] and Black women [OR= 0.15 95% CI: 0.02, 0.94]) during the widespread influenza activity period. However, maternal Influenza vaccination was associated with reduced odds of a preterm birth among white women [OR= 0.34, 95% CI: 0.12, 0.91] and women of higher socio-economic status [OR= 0.30, 95% CI: 0.12, 0.74] during the widespread influenza activity period.

Conclusion:  Influenza vaccination during pregnancy was significantly associated with reduced odds of small for gestational age and preterm births during the widespread influenza activity period. Vaccination effects were stronger among women in higher risk categories.

Saad Omer, PhD, MPH, MBBS, Global Health, Epidemiology, and Pediatrics, Emory University, Rollins School of Public Health, Atlanta, GA, Demilade Adedinsewo, MBChB, MPH, Epidemiology, Emory University, Rollins School of Public Health, Atlanta, GA, Robert Bednarczyk, PhD, Global Health, Emory University, Rollins School of Public Health, Atlanta, GA, Mark C. Steinhoff, M.D., Division of Infectious Diseases, Global Health Center, Cincinnati Children's Hospital Medical Center, Cincinnati, OH and Robert Davis, MD, MPH, Kaiser Permanente Center for Health Research, Atlanta, GA

Disclosures:

S. Omer, None

D. Adedinsewo, None

R. Bednarczyk, None

M. C. Steinhoff, None

R. Davis, None

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