Influenza A H1N1 virus infection among pregnant women in a tertiary hospital in Belgrade, Serbia

Abstract

Introduction: Pregnant women are at higher risk of developing severe influenza. Our aim was to analyze clinical course and risk factors for fatal outcome in pregnant women with influenza (H1N1) infection.

Methodology: This retrospective study enrolled eleven pregnant women with confirmed Influenza A (H1N1) infection treated in the Clinic for Infectious and Tropical Diseases, Belgrade, Serbia in a 6-years period.

Results: The mean age of pregnant women was 28.9 ± 5.2 years, and mean gestational age was 23.1 ± 7.0 weeks. Nine (81.8%) pregnant women had pneumonia (six had interstitial and three had bacterial pneumonia). Pregnant women developed pneumonia more often than other women in the reproductive period, but without statistical significance (81.8% vs. 65.7%, p = 0.330, OR (95% CI) 2.35 (0.47-11.80)). Nine (81.8%) pregnant women recovered. None of them experienced preterm delivery or abortion. Two women (18.2%) died due to acute respiratory distress syndrome. In one of them fetal death occurred one day before she died. The other one was performed caesarean section three days before death. Her newborn and children of all recovered women were healthy at birth. Prolonged time to initiation of oseltamivir and higher body mass index were statistically significantly associated with fatal outcome (p = 0.002, and p = 0.007, respectively). Gestational week of pregnancy, the etiology of pneumonia and comorbidity were not found to be risk factors for death (p = 0.128, p = 0.499 and p = 1.000, respectively).

Conclusion: Pregnant women with H1N1 infection are at higher risk of pneumonia and death than other women in the reproductive period. Early antiviral therapy reduces the risk of unfavorable outcome.

Keywords: Influenza H1N1; oseltamivir; outcome; pregnancy.