Introduction: The 2021-updated guidelines of the Spanish Society of Neonatology Guidelines have moved the zone of parental discretion to 23 + 0-23 + 6 weeks. The objective of this study was to describe the changes in perinatal management at this gestational age along the last decade and to determine if a more active perinatal management has contributed to improved outcomes.
Methods: Retrospective analysis of prospectively collected data from the 23-week infants included in the Spanish SEN 1500 neonatal network during the period 2010-2019. The main study outcomes were survival at discharge and survival without major morbidity of actively managed infants. Two periods were compared: 2010-2014 (Period 1) and 2015-2019 (Period 2). NICUs were classified into low activity NICUs (less than 50 admissions of very low birth weight infants per year) and high activity NICUs (50 or more admissions).
Results: A total of 381 infants were included, 182 in Period 1 and 199 in Period 2. In Period 2 an increase in the use of intrapartum magnesium sulfate (21.5% vs 39.9%, p .002), antenatal steroids (56.6% vs 69.3%, p .011) and active neonatal approach in delivery room (76.9% vs 86.9%, p .011) were observed.The clinical outcomes of the actively managed 313 infants were similar in both periods, except for less arterial hypotension in Period 2. Survival was 27.1% in Period 1 and 25% in Period 2 (p .068) and survival without major morbidity was 2.1% and 2.3% respectively (p .914). No difference was found between low and high activity NICUs.
Conclusion: A change to a more active intention to treat infants born at 23 weeks is taking place in Spain. But the survival rate of the actively-managed infants has remained stable around 25-30% during the study period. A multidisciplinary effort is needed to improve outcomes in this population.
Keywords: 23 weeks; Extreme prematurity; NICU activity; limit of viability; morbidity; mortality; perinatal care.