One in a hundred pregnant females has asthma. Pregnancy may change the course of the asthma and inversely foetal and obstetric prognosis may be affected by the illness and by the potentially deleterious effect of treatment. The maternal physiological changes which occur during pregnancy throw little light on the variations in asthma during pregnancy. Clinical studies in the literature suggest that the quality of follow-up and treatment in patients allows for a satisfactory outcome in pregnancy and that it is an important prognostic factor. Overall, taking account of the pregnancy and confinement the therapeutic approach of the thoracic physician differs little from that in management outside pregnancy. The first objective is to relieve the bronchial obstruction. Broncho-dilator therapy with beta-agonist and by theophylline remains usable in most cases. The side effects of steroid therapy ought to be balanced against the advantages, in order to maintain a normal physiological state. Immunotherapy, and antibiotics should be adapted appropriately for the pregnancy and for their respective contra-indications. Finally, the prevention of atopy should be envisaged.