Pandemic 2009 influenza A (H1N1) in 71 critically ill pregnant women in California.

We sought to describe the characteristics and clinical management of 71 critically ill pregnant women with pandemic 2009 influenza A (H1N1 [2009 H1N1]). This was a retrospective case series from April 23, 2009, through March 18, 2010, of pregnant women with 2009 H1N1 in intensive care units in California. Among 71 critically ill pregnant women with 2009 H1N1, rapid decline in clinical status was noted with a median duration of 1 day from hospital admission to intensive care unit admission. Adverse events were common, and included sepsis (n = 26), hematologic disorder (n = 17), and pneumothorax (n = 15). Of 42 women requiring invasive ventilation, 15 (36%) died. In total, 23 women required rescue therapies for severe gas exchange abnormalities. Adverse events were significantly associated with survival (P = .0003). Women who received early antiviral treatment were significantly more likely to survive (relative risk, 1.43; 95% confidence interval, 1.18-1.75). Critically ill pregnant women with 2009 H1N1 declined rapidly and developed frequent adverse events including death.