(1239) Long-term cardiovascular outcomes in term-born children exposed to antenatal corticosteroids: A population-based cohort study

Antenatal corticosteroids (ACS) are well established in reducing morbidity and mortality among preterm infants. However, the impact of ACS exposure on children born at term remains less clear. This study aimed to evaluate long-term cardiovascular outcomes in term-born offspring exposed to ACS.

Study Design:

We conducted a population-based retrospective cohort study of singleton term deliveries between 1998 and 2021. Long-term cardiovascular morbidity was compared between term-born offspring exposed to ACS before 34 weeks of gestation and unexposed offspring, using linked community and hospitalization databases. The cumulative incidence of cardiovascular morbidity was assessed with Kaplan–Meier survival curves, and the Cox proportional hazards model was used to adjust for potential confounders

Results:
Among 182,626 term deliveries, 2,093 offspring (1.1%) were exposed to ACS before 34 weeks of gestation. The overall incidence of cardiovascular morbidity per 1,000 person-years was significantly higher in the exposed group (Table), with a greater cumulative incidence over time (log-rank 4.42; p = 0.036) (Figure). However, after adjustment for maternal age, gestational age, ethnicity, diabetes mellitus, hypertensive disorders, and mode of delivery, ACS exposure was not significantly associated with cardiovascular morbidity (adjusted hazard ratio [aHR], 1.15; 95% CI, 0.98–1.35; p = 0.068).

Conclusion:
Exposure to antenatal corticosteroids before 34 weeks in pregnancies that reached term was not associated with increased long-term cardiovascular morbidity in offspring after adjustment for confounders. These findings support the cardiovascular safety of ACS use in pregnancies that ultimately result in term delivery.