Pregnant Women Should Get Flu Shots

Several provinces are battling outbreaks of the H1N1 flu virus And Public health officials are redoubling their efforts to convince people to get the flu shot. But pregnant women have long been reluctant to roll up their sleeves. A study published today in the Canadian Medical Association Journal could change that. Pregnant women should get the flu shot because it's good...

CBC Radio Posted: Jan 06, 2014 12:00 AM EST | Last Updated: January 6, 2014

Pregnant women should get the flu shot because it's good for the baby. That's the main conclusion of a study of pregnant women in Nova Scotia by doctors at the IWK Hospital in Halifax. The study was conducted in the two flu seasons following the 2009 H1N1 pandemic, and included more than twelve thousand women who gave birth. Pregnant women who got the flu shot were less likely than non-immunized pregnant women to deliver premature babies. As well, the babies of vaccinated pregnant women had higher birth weights than those born to women who did not get the flu shot. Bottom line: getting a flu shot during pregnancy is good for babies.

Several studies have shown that a flu shot is not just good for the baby but good for pregnant women as well. Pregnant women who get the flu are more likely than women who aren't pregnant to get serious respiratory illnesses. They're more likely to require admission to hospital. If they're admitted to hospital, they're more likely to require admission to ICU. They're also more likely to die from complications. This is true for seasonal influenza. It's also true for H1N1. During the pandemic of 2009, the pregnant women I saw in the ER were sicker than non-pregnant women.

Here's the thing. Despite the benefits, pregnant women are quite reluctant to get the flu shot. A study of women who delivered at the IWK hospital in the years prior to the 2009 H1N1 pandemic found only twenty percent got the shot. In the current study published in CMAJ, in the two years following the pandemic, only sixteen percent of pregnant women got vaccinated. The only relatively bright spot took place during the 2009 pandemic year itself, when sixty-four percent of pregnant women rolled up their sleeves.

One reason is that many Canadians - pregnant women included - harbour misconceptions about the risks of flu shots. One misconception is that you get the flu from a flu shot - which of course you don't. Another factor is that many people have a cognitive bias that says it's always safer to do nothing than to do something. In this example, it's safer both for mum and for baby to refuse the shot than to take it. In the case of a vaccination, all you see is risk without benefit. If you refuse the shot and nothing happens, it reinforces the notion that you did the right thing. So you refuse again.

What can be done to reverse the trend? The article in CMAJ says the US has been far more successful than Canada at boosting flu vaccine rates among pregnant women. The US Centers for Disease Control says during the 2011-2012 flu season, forty-seven percent of pregnant got the shot (compared with twenty percent in Canada). A study by the CDC says nearly half the pregnant women received both a personal recommendation to get the shot and a reminder to do so. Three-quarters of those women who got both were vaccinated. Even women who had reservations about the vaccine took it if their concerns were discussed. This tactic works best when the vaccine is given by the same health professionals who addressed the woman's concerns and in the same place. Still, the US figures show both countries have a long way to go.