Although no teratogenic effects have been observed in animals after administration of bambuterol, caution is recommended during the first trimester of pregnancy. It is not known whether bambuterol or intermediary metabolites pass over to breast milk. Terbutaline passes over to breast milk but an influence on the child is unlikely with therapeutic doses. Transient hypoglycemia has been reported in newborn preterm infants after maternal β2-agonist treatment.
Oral slow-release β2-agonists for asthma and other pulmonary disease should be used with caution at the end of pregnancy because of the tocolytic effect.