Deborah Lehman, MD, associate editor with NEJM Journal Watch Pediatrics and Adolescent Medicine

Infants born to mothers who received flu vaccine during pregnancy have a 60% lower risk for influenza or influenza-­like illness (ILI) in the first 6 months of life than those born to unvaccinated mothers, a Pediatrics study finds. Researchers reviewed records for nearly 250,000 mother­/baby pairs born in Utah and Idaho during influenza seasons from 2005 to 2014.

Overall, 10% reported receiving influenza vaccine during pregnancy. There were no differences in pregnancy outcomes between the vaccinated and unvaccinated groups. During the first 6 months, infants born to vaccinated women had lower rates of ILI evaluation (1.34 vs. 3.70 per 1000), ILI hospitalization (0.17 vs. 1.05), and laboratory­-confirmed influenza (0.84 vs. 2.83). Rates of laboratory­-confirmed respiratory syncytial virus infection did not differ.


This study confirms that maternal influenza vaccination during pregnancy provides protection to infants too young to receive vaccine. These findings should encourage vaccination of all pregnant women to protect the health of their babies.

Personal comment: Pregnant women interact with the health care system very often. Every visit to the obstetrician, emergency room and urgent care center, is an opportunity to offer the recommended flu vaccine. Perhaps if mothers are told that the vaccine could dramatically protect their unborn child, they would be more willing to accept it.


Pediatrics early­release page (Free)

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Background: Physician’s First Watch coverage of influenza vaccine in pregnancy and reduced stillbirth risk(Free)