Evaluation of Survival and Neurodevelopment in Neonates Born Very Preterm at a Tertiary Centre in Portugal

Advances in medical care have significantly improved survival rates for preterm infants globally, leading to an increase of population of newborns at neurological risk. Knowledge of gestational age-specific outcomes is essential to guide and provide the best medical care. This study aimed to evaluate the impact of gestational age in mortality and neurodevelopment of very preterm infants. As a secondary objective, we aimed to determine the influence of perinatal factors on the combined outcome of neurodevelopmental impairment or death.

We conducted a retrospective cohort study of all infants born before completing 32 weeks of gestational age, admitted to the Neonatal Intensive Care Unit in a tertiary maternity hospital in Portugal from 2013 to 2021. Neurodevelopment was assessed at 24 months of corrected age, using Griffiths Mental Developmental Scales II. Moderate to severe neurodevelopment impairment was considered in the presence of at least one of the following criteria: global development quotient < 70, cerebral palsy, severe visual impairment or profound sensorineural deafness.

There were 311 very preterm infants assessed for eligibility, 10.9% neonatal deaths and 11.9% losses to follow-up. Neurodevelopment evaluation was performed on 274 infants, of whom 6.2% (17/274) had moderate to severe neurodevelopment impairment: 7.5% (5/67) born before 28 weeks of gestational age and 5.8% (12/207) between 28 - 31 weeks. Global development quotient < 70 was verified in 4.7% of cases. Cerebral palsy was diagnosed in 3.3%, severe visual impairment in 0.7% and profound sensorineural deafness in 0.7%. The survival rate without moderate to severe neurodevelopment impairment exceeded deaths at 25 weeks and was > 86% from 28 weeks onward. In multivariable logistic regression analysis, gestational age was identified as a protective factor for moderate to severe neurodevelopment impairment or death (aOR 0.81; CI 95% 0.68 - 0.98), whereas male sex (aOR 3.19; CI 95% 1.57 - 6.71) and resuscitation with tracheal intubation (aOR 8.17; CI 95% 3.16 - 20.96) were independent risk factors.

This study reaffirms gestational age as a key determinant of survival and neurodevelopmental outcomes in very preterm infants, with those born before 28 weeks facing higher risks of mortality and severe neurodevelopmental impairments. Understanding local survival rates and neurodevelopmental outcomes is paramount for guiding perinatal decision-making and providing accurate evidence-based counseling to parents of preterm infants.