A case–control study on risk factors associated with death in pregnant women with severe pandemic H1N1 infection

OBJECTIVES: To describe the risk factors associated with death in pregnant women with severe pandemic H1N1 infection. DESIGN: Case–control study. SETTING: Anhui, China. PARTICIPANTS: A total of 46 pregnant women with severe pandemic H1N1 infection were studied during June 2009–April 2011. PRIMARY AND SECONDARY OUTCOME MEASURES: All the cases were confirmed by the clinicians and epidemiologists together based on the positive laboratory result. RESULTS: Of the seven pregnant women who died of the pandemic H1N1 infection, five (70%) cases were in their third trimester. Twenty-nine (63%) cases from the surviving group were admitted to hospital within 3 days after the onset of symptoms, while only one (2%) case from the death group took the earliest admission 2 days after the onset. There was a significant difference on how soon to be admitted between the death and the surviving groups (OR 0.09, 95% CI 0.01 to 0.68). The median time of administrating corticosteroids was 5 days after the onset in the death group and 3 days in the surviving group showing no significant difference between them (p=0.056). CONCLUSIONS: For the pregnant women with severe p(H1N1) infection, the risk factors associated with death were as follows: the delay of antiviral treatment and being in the third trimester. The corticosteroids therapy appeared to have no effects on preventing the cases from death.