Related Experiment Video
Updated: Sep 10, 2025
Assessment and Evaluation of the High Risk Neonate: The NICU Network Neurobehavioral Scale
Published on: August 25, 2014
Outcomes of Preterm Infants Born at 22 to 23 Weeks' Gestation in 11 International Neonatal Networks
Tetsuya Isayama1, Mikael Norman2,3, Satoshi Kusuda4
1Division of Neonatology, National Center for Child Health and Development, Tokyo, Japan.
Insights
Outcomes for extremely preterm infants born at 22-23 weeks gestation vary significantly across international neonatal networks. Identifying these variations is crucial for improving care and research in neonatal intensive care units.
Area of Science:
- Neonatalogy
- Perinatal Medicine
- Public Health
Background:
- Postnatal intensive care for extremely preterm infants (22-23 weeks gestation) is increasing globally.
- Survival rates for this vulnerable population remain low, necessitating research into factors influencing outcomes.
Purpose of the Study:
- To evaluate survival and major morbidities in infants born at 22-23 weeks gestation.
- To assess variations in outcomes among 11 neonatal networks across 12 countries or regions.
Main Methods:
- International registry-based cohort study.
- Inclusion of 5019 neonates born at 22-23 weeks gestation without major congenital anomalies.
- Analysis of data from January 2015 to December 2021.
Main Results:
- Significant variations observed in perinatal management (antenatal steroids, cesarean birth rates) and outcomes (survival, severe periventricular hemorrhage/leukomalacia, retinopathy of prematurity, bronchopulmonary dysplasia, necrotizing enterocolitis) between networks.
- Adjusted probabilities for survival to discharge and major morbidities showed wide confidence intervals, indicating substantial network differences.
- Standardized incidence ratios revealed significant differences in survival and morbidities in some networks compared to a reference population.
Conclusions:
- Substantial international variations exist in the outcomes for extremely preterm infants admitted to neonatal intensive care.
- These variations may stem from differences in healthcare systems, care practices, attitudes, and cultural factors.
- Identifying these variations is key to directing research toward understanding causal determinants and improving care quality.
Importance:
Postnatal intensive care for preterm infants born at 22 to 23 weeks' gestation is increasing, although survival rates remain low. Information on outcomes for multiple countries or regions can be important for research, benchmarking, quality improvement, and parental counseling.
Objective:
To evaluate survival and major morbidities and their between-network variations in infants born at 22 to 23 weeks' gestation in 11 neonatal networks participating in the International Network for Evaluation of Outcomes (iNeo) in neonates in 12 countries or regions.
Design, Setting, And Participants:
International registry-based cohort study of infants born at 22 to 23 weeks' gestation from January 1, 2015, through December 31, 2021, without major congenital anomalies who were admitted for neonatal intensive care in 11 national or regional neonatal consortia. Data analysis was performed from December 2, 2023, to June 15, 2025.
Exposures:
Neonatal consortium and gestational age at birth.
Main Outcomes And Measures:
Survival to neonatal intensive care unit discharge, major neonatal morbidities, and survival without any major morbidities.
Results:
A total of 5019 neonates were included (1084 of 4636 neonates [23%] with a maternal age >35 years; 2641 of 5017 neonates [53%] male); among them, 846 neonates were born at 22 weeks' gestation and 4173 were born at 23 weeks' gestation. Variations between contributing networks for perinatal management at 22 and 23 weeks' gestation, respectively, include any antenatal steroids (ranges of 18%-83% and 57%-98%), cesarean birth (0%-42% and 5%-73%), and outborn (0%-26% and 0%-22%). Significant variations between contributing networks for adjusted probabilities of outcomes at 22 and 23 weeks' gestation, respectively, include survival to discharge (95% CIs of 9%-64% and 16%-80%; P < .001), grade 3 or 4 periventricular hemorrhage (PVH) or periventricular leukomalacia (PVL) (severe PVH or PVL: 24%-65% and 18%-56%; P < .001), survival without severe PVH or PVL (7%-53% and 9%-69%; P < .001), treated retinopathy of prematurity among survivors (32%-57% [P = .008] and 16%-48% [P < .001]), bronchopulmonary dysplasia among survivors (for 23 weeks only: 64%-88%; P < .001), and necrotizing enterocolitis (for 23 weeks only: 6%-28%; P < .001). Standardized incidence ratios showed significant differences in survival and major morbidities in some networks compared with a reference population from all other networks.
Conclusions:
Substantial international variations were identified in outcomes for infants born at 22 to 23 weeks' gestation who were admitted to 11 neonatal networks in the 12 countries or regions. The variations can be due to differences in systems, care practices, attitudes, and culture; however, identification of variation can help focus efforts toward research aimed at understanding the causal determinants of variation.
Related Concept Videos
01:11Guidelines for Writing Outcome
Patient outcomes reflect the patient's response to the goal rather than what the nurse aims to achieve. Terminology should be observable and measurable to avoid the reader's interpretation. The desired outcome should be realistic and achievable in the designated care timeframe. Expected outcomes should align with adjunctive therapies. The outcome should enhance care...
01:29Nursing Interventions II: Selecting and Classifying the Nursing Interventions