Objective. To investigate how pregnant women manage their asthma during pregnancy and factors influencing their behavior. Methods. In-depth interviews (telephone or face-to-face) with a purposive sample of 23 asthmatic women at various stages of pregnancy and with varying severity of sthma. Results. Five major themes were discerned relating to health behavior of pregnant women with asthma. Many of the participants decreased or discontinued their asthma medications themselves and refrained from taking doses when necessary during pregnancy without consulting their doctors. Reasons behind their decisions revolved around lack of support and information about what to do, concerns about the safety of the medications, past experiences, and desire for an a??all naturala?? pregnancy. Asthma monitoring during pregnancy was seen as a low priority for some women and their doctors. Communication between pregnant women and health professionals regarding asthma management was poor. The health behavior of pregnant women with asthma could be explained using the Health Beliefs Model. Conclusions. Pregnant women are not well supported in managing asthma during pregnancy, despite being concerned about outcomes. Interventions, education, and more support are warranted and wanted by pregnant women with asthma to optimize pregnancy and neonatal outcomes.