Asthma is among the diseases that may complicate pregnancy. Asthma affects up to 4% of the pregnant women. Uncontrolled asthma may impair the proper oxygenation of both mother and child. According to asthma severity clinical manifestations may be unapparent or apparent requiring hospital treatment. It is necessary that pregnant asthmatic woman check daily the peak-flow by portable peak-flow meters. The asthma pharmacological treatment should consider the changes in the physiology of the pregnancy, such as low albumin and carrier proteins for the drugs inducing high levels of free active drugs. This point is important for theophylline, besides the low drug clearance. Bronchodilator should be used as they are required, using the inhaled forms, as well as short term corticoid courses. The goal of the treatment is to control the symptoms, avoid relapse and keep the ventilatory function close to the normal, in order to achieve a satisfactory state of the mother and the children.