Asthma in pregnancy: contemporary management

Asthma affects 8% to 13% of pregnancies and is associated with adverse maternal and fetal outcomes. The evidence consistently demonstrates that uncontrolled asthma in pregnancy is the primary driver of this pregnancy risk rather than the diagnosis alone. Compared with controlled disease, uncontrolled asthma has been associated with higher rates of preterm birth (adjusted odds ratio: 1.3 vs 1.6), hypertensive disorders of pregnancy (adjusted odds ratio: 1.2 vs 1.5), and impaired fetal growth or small-for-gestational-age neonates (adjusted odds ratio: 1.2 vs 1.4). This paper aimed to review the biologic pathways linking active asthma to adverse pregnancy outcomes, including airway inflammation, oxidative stress, placental dysfunction, and maternal hypoxemia. Building on modern understanding of asthma heterogeneity, this review integrates phenotype- and endotype-informed principles with pregnancy-specific immunologic shifts, highlighting how a Th2-predominant state may exacerbate disease activity and modify risk in susceptible patients. Multiple modifiable contributors, including viral infections, air pollution, indoor exposures, obesity, allergic rhinitis, gastroesophageal reflux disease, and obstructive sleep apnea, further influence disease activity and underscore the importance of active management. This study synthesizes updated, practical guidance aligned with international asthma guidelines emphasizing proactive monitoring, routine assessment of symptoms and objective measures, and continuation or escalation ("step-up") of controller therapy to maintain control throughout pregnancy. In addition, this study reviewed contemporary strategies for asthma management, including anti-inflammatory reliever therapy and maintenance and reliever therapy, and highlighted nonpharmacologic interventions. Across this review, the emphasis lies on the importance of asthma control, with a goal of complete remission of symptoms, to optimize maternal-fetal outcomes. This study highlights areas of future research, including the implementation of precision-guided asthma care in pregnancy and the use of biologic therapies to prevent active disease.