OBJECTIVE To explore the risk factors for late-onset sepsis （LOS） in very low birth weight infants （VLBWIs）.

METHODS Clinical data of VLBWI admitted to Liaocheng People's Hospital from Jan. 2019 to Dec. 2024 were analyzed. A total of 521 VLBWIs were divided into an LOS group （n=108） and a non-LOS group （n=413） based on the presence or absence of LOS. Multivariate logistic regression analysis was conducted to screen for risk factors for LOS in VLBWI.

RESULTS Among the 521 VLBWIs, LOS occurred in 108 cases （20.73%）. Gram-negative bacteria were the primary infectious pathogens （61.54%）, with Klebsiella pneumoniae being the most common （41.03%）. The 28-day cumulative survival rate in the LOS group was lower than that in the non-LOS group （χ²=11.290, P＜0.001）. Multivariate logistic regression analysis revealed that gestational age （OR=0.539, 95%CI: 0.415－0.700, P＜0.001）, birth weight （OR=0.019, 95%CI: 0.003－0.132, P＜0.001） and endotracheal intubation （OR=2.849, 95%CI: 1.214－6.684, P=0.016） were risk factors for LOS with VLBWIs.

CONCLUSIONS  Gestational age, birth weight and endotracheal intubation are risk factors for LOS in VLBWIs. The combined predictive model of the three risk factors has good predictive value. Clinical attention should be paid to perinatal management to reduce unnecessary invasive procedures, thereby lowering the risk of LOS.