Impact on pregnant women requires more study

Early research studies on H1N1 raised concerns that pregnant women were more significantly affected by H1N1 than by the regular flu. Our study found that the proportion of pregnant women hospitalized with H1N1 was higher than what would be expected in a typical flu year.

From April to December 2009, more than one in five (21%) women of child-bearing age (15 to 44) who were hospitalized with H1N1 were pregnant, compared to 13% of women in this age group who were hospitalized for influenza/pneumonia in 2007-2008. There were four deaths among pregnant women with H1N1 during this time period, compared to no deaths among pregnant women with influenza/pneumonia in all of 2007-2008. ICU use by hospitalized pregnant women was proportionately similar among both H1N1 and baseline influenza/pneumonia patients. In both groups, 12% of ICU patients were pregnant.

"More study is needed to understand why pregnant women account for a higher proportion of hospitalized patients for H1N1 compared to regular influenza/pneumonia," explains Kathleen Morris, head of Emerging Issues at CIHI. "This preliminary comparison will hopefully be a springboard for future research."

Source: CANADIAN INSTITUTE FOR HEALTH INFORMATION