Mother receives Influenza Vaccination while Pregnant, Protects Newborn

According to a recent study, babies born to mothers who received a vaccine for the flu while pregnant are almost 50% less likely to be hospitalized for the flu than babies born to mothers who did not receive the vaccine while pregnant.

The study was performed by researchers at Wake Forest Baptist Medical Center.

According to Katherine A. Poehling, M.D., MPH., an associate professor of pediatrics and lead author on the study, infants under the age of six months suffer from the highest rates of influenza hospitalization among all children, but the flu vaccine is not licensed for/ is not effective in babies so young.

The Advisory Committee on Immunization Practices(ACIP) recommends influenza vaccination for anyone older than six months of age, specifically singling out particular groups such as pregnant women because they can be a greater risk of influenza-related complications.

Given this circumstance, Poehling and her colleagues performed the study in order to determine whether a mother receiving the vaccine during pregnancy would provide some protection for the infant.

The researchers accumulated and examined data gathered by the Centers for Disease Control and Prevention-funded New Vaccine Surveillance Networkbetween the years 2002 and 2009; all data was collected before the H1N1 pandemic.

They analyzed records on roughly 1,510 babies over the course of seven years who had been taken to the hospital suffering from either fever or respiratory symptoms—or sometimes both—within the first six months of life. They also searched for babies who, upon having been taken to the hospital, had received laboratory testing for influenza infection.

The researchers discovered that babies under six months born to mothers who received the influenza vaccine during pregnancy were 45% to 48% less likely to be hospitalized with laboratory-confirmed influenza.

"Similar findings have been published from other studies, but they've been published in general journals or journals about pediatrics and infectious diseases," Poehling said. "Where the information is published really does make a difference because pediatricians need to know about it, but it's even more important that the doctors taking care of pregnant women — obstetricians and gynecologists (OB/GYNs) – know it, too.”

“Pediatricians have been vaccinating children for a long time, but vaccine recommendations for OB/GYNs have changed over the last decade, so everyone is having to learn new recommendations and adjust,” sated Poehling. “This is a relatively new activity for OB/GYNs."

Poehling stated that "it is recommended that all pregnant women receive the influenza vaccine during pregnancy because it is known that pregnant women have increased morbidity and mortality during pregnancy and in the immediate postpartum period if they get the flu.”

"We also know that mothers pass antibodies through the placenta to the baby,” she continued. “This study showed us that receiving the influenza vaccine during pregnancy not only protects the mother, but also protects the baby in the early months of life."

The study appears in the June issue of the American Journal of Obstetrics & Gynecology.