The most commonly reported complication in this study was acute respiratory disease syndrome (ARDS) (151; 53.4%) ( Table 2) . 211 (59.4%) women delivered at a median of 6 days (IQR 3 to 12) after pH1N1 symptom onset. 122 out of 211 women delivered prematurely (Additional file 2: Table S2 ). The most common delivery method was cesarean delivery (172 patients, 82.7%) ( Table 2 ). Among 143 live-birth deliveries for which the gestational age was known, 68 were premature (Additional file 2: Table S2 ). Among the 394 pregnant women in the study, 77 died (Table 2) , 56 out of the 77 patients who died were in their third trimester. The main cause of death was refractory hypoxemia (66 patients, 85.7%). Of 5 patients with secondary infection, three patients had Acinetobacter baumannii, one patient had Aspergillus spp, and one patient had both Acinetobacter baumannii and Aspergillus spp.