Outcome of pregnancy in a randomized controlled study of patients with asthma exposed to budesonide

Background: Budesonide is the only inhaled corticosteroid to be given a category B pregnancy rating by the US Food and Drug Administration, based on observational data from the Swedish Medical Birth Registry. However, data from large randomized controlled trials are lacking. Objective: To compare pregnancy outcomes among patients with recent-onset mild-to-moderate persistent asthma receiving low-dose budesonide vs placebo. Methods: In a randomized, double-blind, placebo-controlled trial, 7,241 patients aged 5 to 66 years with mild-to-moderate persistent asthma for less than 2 years and no previous regular corticosteroid therapy received once-daily budesonide or placebo via dry powder inhaler in addition to their usual asthma medication for 3 years. This trial was followed by a 2-year open-label treatment period. The daily dose of budesonide was 400 mu g for adults. The study included 2,473 females aged 15 to 50 years at randomization. Pregnancy was not an exclusion criterion (except for US patients). Results: Of 319 pregnancies reported, 313 were analyzed. Healthy children were delivered in 81% and 77% of all pregnancies in the budesonide and placebo groups, respectively. Of the 196 pregnancies reported by participants taking budesonide, 38 (19%) had adverse outcomes: 23 (12%) had miscarriages, 3 (2%) had congenital malformations, and 12 (6%) had other outcomes. 01 the 117 pregnancies reported in the placebo group, 27 (23%) had adverse outcomes: 11 (9%) had miscarriages, 4 (3%) had congenital malformations, and 12 (10%) had other outcomes. Conclusions: Treatment with low-dose inhaled budesonide in females with mild-to-moderate persistent asthma does not seem to affect the outcome of pregnancy.