Introduction

Extreme preterm infants (EPI), born at <26 weeks’ gestation and weighing <750 g, represent the most vulnerable subset of preterm neonates with the highest risk of mortality and major morbidities. Despite significant advances in neonatal/perinatal care, outcomes for this population remain a major clinical challenge.

Objective

To evaluate temporal trends in survival, morbidity profiles, and predictors of in-hospital survival among inborn extreme preterm infants of birth weight <750 g and gestational age < 26 weeks over an 18-year period in a tertiary-level neonatal intensive care unit (NICU).

Methods

This retrospective cohort study included 134 inborn EP infants admitted between 2002 and 2019. The primary outcome was survival to hospital discharge; secondary outcomes included rates of several prematurity-related morbidities. Multivariable logistic regression was used to identify independent predictors of survival.

Results

Survival to discharge increased over time from 29% (2002–2007) to 61% (2014–2019) (p = 0.009). Antenatal corticosteroid (ACS) (a OR 2.9, 95% CI 1.05–8.04, p = 0.049) and cesarean delivery (aOR 2.88, 95% CI 1.03–8.07, p = 0.044) were independently associated with increased odds of survival. Early hypotension (aOR 0.28, 95% CI 0.12–0.67, p = 0.004) and severe IVH (aOR 0.39, 95% CI 0.16–0.94, p = 0.035) were significantly associated with increased mortality. The incidence of severe IVH declined from 46% to 26% over the study period, while rates of PVL and surgical NEC showed downward trends. BPD (51%) and severe ROP (19%) remained relatively unchanged.

Conclusions

Over nearly two decades, survival among extreme preterm infants of birth weight <750 g ang gestational age <26 weeks improved significantly. ACS administration and cesarean birth were associated with an increased rate of survival. Early hypotension and severe IVH were predictors of mortality. Severe IVH, PVL, and surgical NEC declined during the last period. Ongoing advances in perinatal care and targeted neonatal interventions are essential to further improve outcomes in this high-risk population.