Do Birthweight-For-Gestational Age Centiles Predict Serious Neonatal Morbidity and Neonatal Mortality?

Area of Science:

• Neonatal Health
• Predictive Modeling
• Perinatal Epidemiology

Background:

• Foetal and birthweight-for-gestational age centiles are insufficient predictors of serious neonatal morbidity and mortality (SNMM) in univariable analyses.
• Existing models often fail to accurately identify neonates at high risk.

Purpose of the Study:

• To evaluate the predictive performance of multivariable SNMM models.
• To assess the impact of including birthweight centiles in these models.

Main Methods:

• Utilized US live birth data (2019-2021) from the National Center for Health Statistics.
• Defined SNMM by Apgar score, seizures, assisted ventilation, or neonatal death.
• Developed log-linear regression models using maternal/pregnancy characteristics, with and without birthweight centiles, for various gestational ages and maternal conditions.
• Assessed model performance using the area under the curve (AUC).

Main Results:

• Models for all live births (24-42 weeks) showed AUCs of 0.83, with minimal improvement from birthweight centiles.
• For 39-week gestation births, AUCs were 0.66 (without centiles) and 0.69 (with centiles).
• For births to mothers with pre-existing diabetes at 39 weeks, AUCs increased from 0.69 to 0.77 with birthweight centiles.

Conclusions:

• Birthweight centiles enhance the predictive accuracy of multivariable SNMM models in specific subpopulations, such as those with pre-existing diabetes.
• Clinical utility depends on evaluating decision thresholds to ascertain the importance of these predictive improvements.