Clinical predictors of length of stay among neonates admitted to a NICU in a secondary referral hospital in Indonesia

Background. Length of stay (LOS) in the neonatal intensive care units (NICUs) shows illness severity and healthcare resource utilization. Longer hospitalizations raise the risk of complications and impose substantial economic and psychosocial burdens on families. Evidence regarding the factors influencing NICU LOS in secondary referral hospitals in Indonesia remains limited. Materials and methods. This retrospective observational study included 97 neonates admitted to the NICU of a secondary referral hospital in Indonesia between August 2024 and August 2025. Independent variables were sex, mode of delivery, gestational age, birth weight, Apgar scores, age at initiation of trophic feeding, and oxygen support category. LOS was measured in days. Mann-Whitney U and Pearson-Spearman correlation tests were used for bivariate analysis. Variables with p < 0.10 were entered into a multivariable Poisson regression model to identify independent predictors of LOS. Results. The median LOS was 10 days (interquartile range 11; range 3–72 days), and the mean was 13.65 days. Bivariate analysis showed significant associations between LOS and gestational age (p < 0.001), birth weight (p < 0.001), Apgar score at 5 minutes (p = 0.029), age at trophic feeding initiation (p < 0.001), and oxygen support category (p = 0.002). In the multivariable analysis, each additional week of gestational age was associated with a lower LOS (adjusted rate ratio (aRR) = 0.25; 95% confidence interval (CI): 0.06–0.98; p = 0.047). Each 100 g rise in birth weight also reduced LOS (aRR = 0.16; 95% CI: 0.04–0.69; p = 0.002). On the other hand, each day of delay in initiating trophic feeding was associated with a higher LOS (aRR = 2.68; 95% CI: 1.05–6.86; p = 0.039). Conclusions. Gestational age, birth weight, and the timing of trophic feeding were strong predictors of NICU length of stay. Early identification of high-risk neonates and timely initiation of enteral feeding may help shorten hospitalization and improve resource utilization. This is particularly important for NICUs in resource-limited hospitals.