Effects of influenza on pregnant women and infants.

Influenza vaccination during pregnancy has been shown to decrease the risk of influenza and its complications among pregnant women and their infants up to 6 months old. To adequately assess the benefits and potential risks that are associated with the use of influenza vaccine during pregnancy, it is necessary to examine the influenza-associated complications that occur among pregnant women and their children. Pregnant women have been shown to be at increased risk for morbidity and death with influenza illness during seasonal epidemics and pandemics. Newborn infants born to mothers with influenza during pregnancy, especially mothers with severe illness, are at increased risk of adverse outcomes, such as preterm birth and low birthweight. Infants <6 months old who experience influenza virus infection have the highest rates of hospitalization and death of all children. Here we review the risks for influenza-associated complications among pregnant women and infants <6 months old.