Related Experiment Video
Updated: Dec 18, 2025
The Perinatal Asphyxiated Lamb Model: A Model for Newborn Resuscitation
Published on: August 15, 2018
Survival Without Major Morbidity Among Very Low Birth Weight Infants in California
Henry C Lee1,2, Jessica Liu3,2, Jochen Profit3,2
1Perinatal Epidemiology and Health Outcomes Research Unit, Division of Neonatal and Developmental Medicine, Department of Pediatrics, School of Medicine, Stanford University, Stanford, California; and hclee@stanford.edu.
Insights
Survival without major morbidity for very low birth weight infants improved from 2008-2017. Bronchopulmonary dysplasia remains a key target for quality improvement efforts in neonatal care.
Area of Science:
- Neonatalogy
- Pediatric critical care
- Public health
Background:
- Survival without major morbidity is a critical outcome for very low birth weight (VLBW) infants.
- Understanding trends and variations in VLBW infant outcomes is essential for quality improvement.
Purpose of the Study:
- To examine trends in survival without major morbidity among VLBW infants in California.
- To identify remaining gaps and opportunities for improvement in VLBW infant care.
Main Methods:
- Analysis of a cohort of 49,333 VLBW infants born between 2008 and 2017 across 142 California hospitals.
- Risk-adjusted trends of survival without major morbidity and its components were analyzed.
- Simulation of top-quartile performance to estimate potential benefits of improvement.
Main Results:
- Survival without major morbidity increased from 62.2% to 66.9% between 2008 and 2017.
- Significant improvements were observed in necrotizing enterocolitis and nosocomial infection rates.
- Bronchopulmonary dysplasia rates showed no significant change, indicating a persistent challenge.
Conclusions:
- While overall survival without major morbidity has improved, bronchopulmonary dysplasia remains a significant concern.
- Targeted quality improvement efforts focused on bronchopulmonary dysplasia are crucial for further enhancing VLBW infant outcomes.
Objectives:
To examine trends in survival without major morbidity and its individual components among very low birth weight infants across California and assess remaining gaps that may be opportune targets for improvement efforts.
Methods:
The study population included infants born between 2008 and 2017 with birth weights of 401 to 1500 g or a gestational age of 22 to 29 weeks. Risk-adjusted trends of survival without major morbidity and its individual components were analyzed. Survival without major morbidity was defined as the absence of death during birth hospitalization, chronic lung disease, severe peri-intraventricular hemorrhage, nosocomial infection, necrotizing enterocolitis, severe retinopathy of prematurity or related surgery, and cystic periventricular leukomalacia. Variations in adjusted rates and/or interquartile ranges were examined. To assess opportunities for additional improvement, all hospitals were reassigned to perform as if in the top quartile, and recalculation of predicted numbers were used to estimate potential benefit.
Results:
In this cohort of 49 333 infants across 142 hospitals, survival without major morbidity consistently increased from 62.2% to 66.9% from 2008 to 2017. Network variation decreased, with interquartile ranges decreasing from 21.1% to 19.2%. The largest improvements were seen for necrotizing enterocolitis and nosocomial infection. Bronchopulmonary dysplasia rates did not change significantly. Over the final 3 years, if all hospitals performed as well as the top quartile, an additional 621 infants per year would have survived without major morbidity, accounting for an additional 6.6% annual improvement.
Conclusions:
Although trends are promising, bronchopulmonary dysplasia remains a common and persistent major morbidity, remaining a target for continued quality-improvement efforts.
