Neonatal outcome in gestational-diabetic mothers treated with antenatal corticosteroids delivering at the late preterm and term

Objective: To determine the association between antenatal corticosteroid treatment and neonatal complications in diabetic mothers delivering after 34 weeks of gestation. Methods: A retrospective cohort study of women with singleton pregnancies diagnosed with gestational diabetes who delivered after 34 weeks of gestation in a university-affiliated medical center (2012–2016). Mothers treated with corticosteroids prior to 34 + 0 weeks of gestation were divided according to gestational age at delivery: late-preterm (34 + 0 to 36 + 6) and term (37 + 0 to 41 + 6). Each group was compared to women delivering at the same gestational age who were not treated with corticosteroids. Primary outcome was defined as a neonatal adverse composite outcome. Birth weight was amongst secondary outcomes measured. Logistic regression analysis was utilized to adjust results to potential confounders. Results: During the study period, 161 diabetic mothers delivered at late-preterm. Amongst them, 47 (30%) were treated with corticosteroids. 2101 diabetic mothers delivered at term, amongst them 82 (4%) were treated with corticosteroids. Primary outcome did not differ between groups. Multivariate analysis demonstrated that corticosteroid treatment was not associated with neonatal adverse composite outcome when delivery occurred at the late preterm, nor at term (adjusted odds ratio (aOR) = 0.708, 95% CI 0.2–2.3, p = 0.572, and aOR = 1.6, 95% CI 0.2–12.7, p = 0.635, respectively). Birth weight was significantly lower in women treated with corticosteroids (2486 vs. 2675 g, p = 0.02 at late-preterm, and 3160 vs. 3319 g, p < 0.001 at term). Conclusion: Corticosteroid treatment for diabetic mothers was not associated with neonatal adverse outcomes, but was found associated with a lower birth weight, when delivery occurs after 34 weeks of gestation.