Researchers have found that pregnant women who get their flu shots a month or more before delivery provide influenza protection to their babies during their first six months. The study, conducted in Bangladesh and led by Mark C. Steinhoff, MD, at Baltimore's Johns Hopkins University, has shown that flu vaccines can provide protection to both the mother as well as her baby.

Steinhoff said in a news release, "Our study shows that a newborn's risk of infection can be greatly reduced by vaccinating Mom during pregnancy. It's a two-for-one benefit. Infants under six months have the highest rates of hospitalization from influenza among children in the U.S."

Though pregnant women are advised by the U.S. Centers for Disease Control and Prevention guidelines since 1997 to get their flu shots only 12- 13% actually do so. These shots are not licensed for infants under the age of six months and they are therefore more likely to be hospitalized for influenza than any other age group. "Immunize the mother and you protect the infant," said Steinhoff.

The study appears in the Sept 17 Online First issue of The New England Journal of Medicine, conducted tests on 340 pregnant women in Bangladesh. The results showed that the shots reduced flu risk by 63 % and the risk of respiratory illness overall by 29%. In the vaccinated group there were six confirmed cases of influenza as compared to 16 among the mothers given a different vaccine. The injections also lowered the likelihood of fever and respiratory illness among the mothers by 36%.

Though medical experts have known for a while now that vaccines given to a pregnant woman can provide protection to her baby, Steinhoff said, "We always assumed it, but nobody's done the study before," he said. "This might persuade more mothers to say, 'Hey, it really helps me and it really helps the baby,'" Steinhoff added.

Currently pregnant women are advised to get the vaccine during the flu season, although it takes about a month for the protection to build in the baby. In the study undertaken in Bangladesh the vaccines were given during the third trimester. Steinhoff explains that, "at the time we did the study, that was the recommendation," he said.
Pregnant women should be encouraged to be vaccinated for the flu to protect their infants and themselves," Steinhoff concluded. .

Researchers from the International Center for Diarrheal Disease Research in Dhaka, Bangladesh, and from Emory University in Atlanta also contributed to the study.