[Report: complicated influenza A(H1N1) in a second-trimester pregnancy].

A 27-year-old woman at 25 weeks of gestation was admitted to hospital due to bilateral pneumonia with increasing hypoxia. She was tested positive for influenza A (H1N1) and successfully treated with oral oseltamivir. Nine days after the admission pathological umbilical flows were recorded and an emergency caesarean was performed at 26 weeks + 2 days of gestation. The neonatal period was uncomplicated. Influenza A (H1N1) is especially dangerous in pregnant women and vaccination is important.