Asthma is considered to be the most common respiratory disorder complicating pregnancy. Seventy-six asthmatic and 152 non-asthmatic pregnant women were studied. Maternal asthma was significantly associated with adverse infant outcomes, including prematurity, low birth weight and the need for Cesarean delivery. The results of this study could indicate that pregnant women with asthma were at substantially increased risk for adverse infant outcomes and suggest the need for extra attention to mothers with asthma before and during pregnancy.