Infant respiratory outcomes following asthma management and exacerbations in pregnancy

Improved maternal asthma management in pregnancy may reduce recurrent bronchiolitis and wheeze outcomes in infancy. We assessed whether infant bronchiolitis and wheeze outcomes are influenced by inflammation-guided management intervention, inhaled corticosteroid (ICS) use or exacerbations in pregnancy.

A randomised controlled trial (RCT) secondary analysis and observational cohort analysis using the same study population was carried out. Pregnant women (12-23 weeks' gestation) from six centres in Australia were recruited and randomised to inflammation-guided asthma management or usual care between 2013 and 2023. ICS use and asthma exacerbations were reported during pregnancy and postnatally. When infants were 6 (n=691) and 12 (n=606) months of age, respiratory information was collected from parents and medical records. Associations for the RCT and observational analyses were assessed with logistic regression.

Guided asthma management in pregnancy was not associated with bronchiolitis or wheeze-related outcomes, for example for recurrent bronchiolitis at 12 months, the intervention OR was 1.04 (95% CI 0.62-1.73). In the observational analyses, ICS use in pregnancy was not associated with respiratory outcomes; however, asthma exacerbations in pregnancy were associated with at least one bronchiolitis episode (adjusted odds ratio (adjOR) 2.20, 95% CI 1.28-3.76) or croup episode (adjOR 4.34, 95% CI 1.89-9.96) at 6 months, and wheeze (adjOR 1.80, 95% CI 1.14-2.84) and increasing wheeze episodes at 12 months (adjOR 1.81, 95% CI 1.17-2.79).

Although there was no evidence that guided asthma management or ICS use in pregnancy reduces infant bronchiolitis or wheeze, maternal asthma exacerbations are an important risk factor for these outcomes. Further research is needed to reduce exacerbations in pregnancy.