ACOG practice bulletin: clinical management guidelines for obstetrician-gynecologists number 90, February 2008: asthma in pregnancy.

Asthma is a common, potentially serious medical condition that complicates approximately 4-8% of pregnancies. In general, the prevalence of and morbidity from asthma are increasing, although asthma mortality rates have decreased in recent years. The purpose of this document is to review the best available evidence about the management of asthma during pregnancy.