Pregnant women with asthma who kept using inhaled corticosteroids (ICS) during the first trimester faced no greater risk of serious maternal or neonatal complications compared to those who stopped — yet nearly two-thirds of women in the study discontinued treatment anyway. The findings, published in JAMA Network Open, reinforce existing guidelines recommending continued ICS use throughout pregnancy to maintain asthma control.

The nationwide cohort study analyzed over 6,100 pregnancies in South Korea between 2010 and 2022. Researchers found no statistically significant differences between the continuation and discontinuation groups across a wide range of outcomes. Experts warn that poorly controlled asthma — not the medication — is the real danger, potentially leading to hospitalizations, asthma exacerbations requiring ICU-level care, and worse outcomes for both mother and baby.

Key Takeaways:

• No significant increase in preeclampsia, gestational diabetes, obstructed labor, antepartum hemorrhage, or preterm birth with continued ICS use
• No significant increase in neonatal hypoxia/asphyxia, low birth weight, or congenital malformations
• ~65% of women with asthma stopped ICS in the first trimester despite guideline recommendations
• Women using ICS/LABA combinations or with more frequent respiratory visits were more likely to continue ICS

Why it matters: Many pregnant patients stop their inhalers out of concern for their baby — but untreated asthma carries its own serious risks. Clinicians should proactively reassure patients, check inhaler technique, and emphasize that maintaining asthma control is essential for the health of both mother and baby.