Continuing Inhaled Corticosteroids Appeared Safe in Early Pregnancy

Continuing inhaled corticosteroids (ICSs) during the first trimester was not associated with increased maternal or neonatal risks among women with asthma, according to a nationwide cohort study published in JAMA Network Open. The analysis compared outcomes among 6105 pregnancies with prepregnancy ICS use.

Investigators used linked South Korean health care data covering live births from April 2010 through December 2022. Eligible women were aged 15 to 50 years, had asthma, and received at least 2 ICS prescriptions during the 6 months before their last menstrual period. Continuation was defined as at least 1 first-trimester ICS prescription; 2108 women continued treatment and 3997 discontinued it.

After propensity score overlap weighting, continuation was not significantly associated with any assessed outcome. Risks per 1000 pregnancies for continuation vs discontinuation were 145.6 vs 131.9 for gestational diabetes (weighted risk ratio [RR], 1.05; 95% CI, 0.90-1.22), 131.4 vs 128.6 for preterm birth (RR, 0.95; 95% CI, 0.82-1.11), 77.5 vs 58.3 for low birth weight (RR, 1.11; 95% CI, 0.89-1.39), and 57.6 vs 42.2 for congenital malformations (RR, 1.22; 95% CI, 0.94-1.56).

No significant differences were found for preeclampsia, obstructed labor, antepartum hemorrhage, premature rupture of membranes, or neonatal hypoxia or asphyxia. Results were consistent across subgroup and sensitivity analyses. However, prescription records could not confirm actual use, residual confounding remained possible, and the cohort excluded pregnancies ending in miscarriage, stillbirth, or termination.

The investigators said the findings provide reassuring evidence for continuing ICS therapy during pregnancy when clinically indicated to maintain asthma control, while emphasizing individualized risk assessment. Because the study was observational, the results describe associations and do not establish causal effects.

Source: Suh B, Cho Y, Choi EY, et al. Inhaled corticosteroids continuation in the first trimester and pregnancy outcomes in women with asthma. JAMA Netw Open. 2026;9(8):e2630781. doi:10.1001/jamanetworkopen.2026.30781