Few prospective clinical trials exist to address the use of asthma medications during pregnancy in relation to neonatal outcomes. There is a need to identify favorable pregnancy outcomes in relation to the successful treatment of pregnant women with asthma. To this end, 3 studies have been initiated: (1) a retrospective analysis of inhaled steroid use in a maternal-fetal medicine research center, (2) a large observational cohort study assessing the effects of different types of asthma treatments on perinatal outcomes, and (3) a randomized clinical trial comparing theophylline and inhaled beclomethasone in the treatment of pregnant women with moderately severe asthma. Preliminary information on all 3 studies is described.