Antenatal corticosteroids in diabetic pregnancies and outcomes of very preterm infants: a national multicenter cohort study.

Antenatal corticosteroids (ACS) can improve the outcomes of preterm infants and have been widely adopted as the standard practice in managing pregnancies at high risk of preterm delivery between 22+0 and 33+6 weeks. Due to their significant benefit for the majority of pregnant women, several guidelines also state that maternal diabetes is not a contraindication for the use of ACS. However, no such evidence has been obtained from diabetic pregnancies. The Chinese Neonatal Network (CHNN), a national multicenter cohort study, recruited 31,915 very preterm infants (VPIs) from 79 NICUs. The outcomes were mortality and morbidity in hospital. Logistic regression models were employed to calculate the odds ratios (ORs) and its 95% confidence intervals (CIs) to estimate the associations between ACS and these outcomes. Stratification and sensitivity analyses were conducted to test the robustness of the results in different population. A total of 4337 VPIs born to diabetic mothers enrolled in the present study: 3605 VPIs were exposed to ACS and 732 were not. ACS was associated with a lower risk in the combined outcome (death or any severe morbidity) (adjusted OR [aOR] 0.66, 95% CI 0.54-0.79), in-hospital death (aOR 0.55, 95% CI 0.41-0.73), severe bronchopulmonary dysplasia (BPD, aOR 0.69, 95% CI 0.55-0.85), low Apgar score (aOR 0.76, 95% CI 0.61-0.96), respiratory distress syndrome (RDS, aOR 0.79, 95% CI 0.66-0.94), or the need for invasive ventilation (aOR 0.62, 95% CI 0.52-0.73). However, a significantly higher risk of maternal chorioamnionitis (aOR 2.09, 95% CI 1.61-2.72) was observed in the ACS group. Similar results were observed in stratification and sensitivity analyses. Conclusions: In VPIs of diabetic mothers, ACS exposure was associated with lower mortality and reduced risks of BPD, low Apgar score, RDS, and invasive ventilation, but with higher odds of maternal chorioamnionitis. What is Known: • Antenatal corticosteroids (ACS) are standard care for reducing neonatal morbidity and mortality in pregnancies at high risk of preterm birth between 22+0 and 33+6 weeks. • However, recommendations for ACS use in pregnant women with diabetes at risk of preterm delivery remain inconsistent due to limited evidence.  What is New: • This large, national multicenter cohort study provides the first specific evidence that ACS administration in diabetic pregnancies is associated with significantly lower risks of neonatal mortality, bronchopulmonary dysplasia, respiratory distress syndrome, and the need for invasive ventilation. • Our findings support the benefit of ACS in this understudied population, demonstrating a favorable risk-benefit profile.