Flu Shots for Expectant Mothers Add to Babies’ Birth Weight

[Guest guest]

This study is ridiculous on so many points. First, there were only 340 women studied in two time periods within one year (one period for when flu was circulating, one without). Assuming the groups were evenly split so there were 170 in each time period, and assuming each time period had 85 vaxed, 85 not, it's an absurdly small study. And what if they split it unevenly (which does happen)? That skews the sketchy statistics even further.

Second, the group tested when the flu was not circulating showed NO DIFFERENCE in birth weight. This is important, but dismissed. The group tested when the flu WAS circulating showed a slightly higher birth weight in the vaxed group. The results really were based on whether the flu was circulating. Yet, they cherry pick the results to give the vaccine credit and the headline flatly states it's true!

Winnie

(http://www.nytimes.com/2012/02/28/health/flu-shots-for-expectant-mothers-add-to-babies-birth-weight.html?src=recg)

Flu: Flu Shots for Expectant Mothers Add to Babies’ Birth Weight By DONALD G. McNEIL Jr.

Flu shots for mothers appear to increase the birth weights of their babies, making it more likely they will survive, according to a new study done in Bangladesh.

Because the study was small but promising, the researchers received a $10 million grant from the Bill and Melinda Gates Foundation to begin a larger one in Nepal.

The Bangladesh study, published last week in The Canadian Medical Association Journal, involved 340 urban women. The Nepali one will enroll 3,600.

When it was not flu season, there was no weight difference between babies of women who did or did not get flu shots. But during flu season, mothers who got shots in their last trimester gave birth to babies almost seven ounces heavier on average.

Studies in two American states, Canada and Britain looking at women who voluntarily got flu shots also have found that they gave birth to babies 3 to 10 ounces larger than those of women who did not receive flu shots, said Dr. Mark C. Steinhoff, director of children’s global health at Cincinnati Children’s Hospital Medical Center and the leader of the two Southeast Asian studies.

The flu season in tropical Asia is less well defined than in wintry climes, Dr. Steinhoff said. But the season can last longer, and which influenza strains are circulating can shift radically when the monsoon rains change direction, meaning the vaccines may also have to be changed.

“It’s really complicated,” he said.