Obstetric, clinical, and perinatal implications of H1N1 viral infection during pregnancy.

OBJECTIVE: To determine perinatal outcome and epidemiologic, clinical, and obstetric characteristics among pregnant women infected with the H1N1 virus admitted to a Brazilian university hospital.
METHODS: A cross-sectional study was conducted of pregnant women infected with H1N1 who were admitted to the University Hospital at the School of Medicine, Federal University of Mato Grosso do Sul, Campo Grande, Brazil, during the 2009 pandemic. Data were obtained via a questionnaire, which was administered during the hospital evaluation of patients' medical records.
RESULTS: Thirty-one patients were included in the study. Antiviral therapy was initiated within 48 hours of the onset of symptoms in 64.5% of cases. Infection with the H1N1 virus was associated with severe clinical complications in 22.6% of patients and adverse perinatal outcomes in 41.9% of cases. The rate of maternal and perinatal mortality was 9.7%. There was a statistically significant association between late treatment with oseltamivir and increase in systemic complications in pregnancy (odds ratio 22.80 [95% confidence interval, 2.20-235.65]; P=0.007).
CONCLUSION: Early treatment with oseltamivir may prevent serious complications associated with H1N1 infection in pregnant women but it does not affect perinatal outcome.