These findings confirm those of previous studies that cleft palate and gastroschisis are associated with first-trimester exposure to β2-agonists. The study authors consider these risks to be low for the individual women and that the risks of uncontrolled asthma might be considerably greater.
For inhaled corticosteroids, no specific congenital anomalies with first-trimester exposure were identified. However, an exploratory analysis identified renal dysplasia with exposure to the combination product of inhaled long-acting β2-agonists and corticosteroids which requires further investigation.
Overall, the study authors note that “both maternal asthma and asthma exacerbation during the first trimester of pregnancy have been found to increase the risk of congenital anomalies. Further asthma exacerbations during pregnancy have been associated with other unfavorable pregnancy outcomes for both the mother and infant. Use of prophylactic inhaled steroids seems to be the best solution for treatment of asthma in pregnancy to prevent asthma exacerbations and to reduce the need for β2-agonists.”
British Thoracic Society asthma guidance (2014) recommends the use of β2-agonists and inhaled corticosteroids as normal for asthma during pregnancy.