Average Treatment Effects of a Single-dose Antenatal Corticosteroid on the Respiratory Morbidity of Filipino Preterm Neonates

Introduction. Prematurity-related respiratory disorders are an important public health concern that should betreated efficiently and effectively. Antenatal corticosteroid (ACS) therapy has been recommended to hasten fetallung maturation in pregnancies at risk but has not been delivered adequately in low to middle-income countries. This study aimed to estimate the treatment effects associated with the use of a single-dose antenatal corticosteroid on the incidence of respiratory-associated morbidity among prematurely delivered neonates.Methods. This was a retrospective cohort study of neonates delivered at 24 to 33 weeks gestation at a tertiaryhospital comparing outcomes in those given single-dose ACS with those given no ACS. Association was estimated using logistic and propensity score (PS) analyses, as well as average treatment effect (ATE) and among those treated (ATET).Results. Most neonates (78.11%) received a single dose before delivery (single-dose ACS group) and only a few(21.89%) did not receive any dose (no ACS dose group). The odds ratio of respiratory morbidity in the single-dose ACS group was 0.44 (0.23-0.84) from an adjusted logistic regression model and 0.33 (0.17-0.80) from the PS matching model. The latter model was used to estimate that the average treatment effect from a single-ACS dose on the entire sample was -0.09 (-0.03 to -0.15), while its effect among the actual recipients was -0.08 (-0.02 to -0.15).Conclusion. There is a small benefit attributed to the single-dose ACS, reinforcing the need for dose administration and completion. Future studies are recommended to clarify the estimated association and improve on the methodological constraints encountered.