Studies that compare the systemic impact of inhaled corticosteroids (CI) abound in the literature often with contradictory results. Most of the studies report secondary biological effects in the suprarenal function without clinical effect due to taking high doses of inhaled corticosteroids. Surveillance of the secondary effects on bone is difficult to demonstrate. Finally, speed for recognition in asthmatic children during the first year of treatment is slowed down but the level at adult age is not affected. The variability of these results is associated with the former taking of corticosteroids by the general route. Administration of corticosteroids by the systemic route, therefore makes difficult the evaluation of secondary effects due only taking inhaled corticosteroids.

Drugs administrated to pregnant women must be carefully monitored. Prevention of dietary sensitization in foetus via the mother is still discussed. However, it must not induce any dietary deficiency to both the mother and the foetus. Environmental prevention is also controversial. Asthmatic pregnant women must be treated because under- or non treatment is more dangerous for both the woman and the foetus compared to eventual drug side effect. Asthma must be treated with inhaled glucocorticosteroid in order to be stabilized because giving birth is the only moment which can not be interrupted. Antihistamine-H1 which can be used during pregnancy are dexchlorpheniramine for the first and second third and cetirizine during the last third of the pregnancy.