Maternal and Neonatal Factors Associated with Length of Hospital Stay and Clinical Outcomes among Neonates with Respiratory Distress Syndrome: A Retrospective Cohort Study

Abstract

Background: Respiratory distress syndrome (RDS) is a major contributor to neonatal morbidity and prolonged length of stay (LOS) in neonatal intensive care units (NICUs). This study examined the associations of maternal and neonatal factors with LOS among neonates with RDS admitted to the NICU of Ir. Soekarno Regional General Hospital, Morotai Island Regency, Indonesia. Methods: This retrospective analytical cohort study included all 33 eligible neonates diagnosed with RDS who were discharged alive from the NICU between October and November 2025. Secondary data were extracted from medical records using a standardized case report form. The independent variables comprised maternal and neonatal characteristics (gestational age, APGAR Score, Amniotic fluid condition, birth weight, SpO2, mode of delivery, respiration rate and  WBC) while the primary outcome was hospital LOS, measured in days. Bivariate analyses were performed using the Mann–Whitney U test and Spearman’s rank correlation. Variables meeting the prespecified exploratory threshold of p < 0.25 were subsequently entered into a multivariable Poisson regression model, with adjusted incidence rate ratios (aIRRs) and 95% confidence intervals (CIs) reported as measures of association. Results: The median LOS was 4 days (interquartile range: 3.0–5.5 days). Most neonates were born at term (72.7%), and the mean birth weight was 2,983.2 ± 752.6 g. In the bivariate analyses, birth weight (p = 0.080), peripheral oxygen saturation (SpO₂; p = 0.106), and mode of delivery (p = 0.126) met the prespecified criterion for inclusion in the multivariable model. No evidence of overdispersion was observed (deviance/df = 0.619), although the overall model was not statistically significant (p = 0.419). After simultaneous adjustment, each 100-g increase in birth weight was associated with an estimated 0.8% reduction in LOS, but the association was not statistically significant (aIRR = 0.992; p = 0.578). SpO₂ (aIRR = 0.990; p = 0.803) and mode of delivery (aIRR = 0.782; p = 0.251) were likewise not independently associated with LOS. Conclusions: Birth weight, SpO₂, and mode of delivery were not independently associated with LOS among neonates with RDS who survived to hospital discharge. These findings should be interpreted cautiously because of the small sample size, short observation period, and restriction of the analysis to survivors. Larger multicentre studies incorporating indicators of disease severity and treatment-related factors are warranted.