Customized versus population approach for evaluation of fetal overgrowth

Area of Science:

• Perinatal medicine
• Neonatal outcomes
• Fetal growth assessment

Background:

• Accurate identification of neonates at risk for adverse perinatal outcomes (APOs) associated with fetal overgrowth and gestational diabetes (GDM) is crucial.
• Current methods utilize population-based or customized fetal growth norms, but their comparative effectiveness in identifying these at-risk neonates is not fully understood.

Purpose of the Study:

• To compare the efficacy of customized versus normalized population fetal growth norms in identifying neonates at risk for APOs.
• To assess the predictive accuracy of these norms for specific neonatal complications related to fetal overgrowth and GDM.

Main Methods:

• Secondary analysis of a multicenter trial for mild GDM.
• Birth weight percentiles were calculated using both ethnicity- and gender-specific population norms and customized (Gardosi) norms.
• The primary outcome was a composite of neonatal outcomes associated with fetal overgrowth and GDM.

Main Results:

• More neonates were classified as large for gestational age (LGA) using customized norms (13.8%) compared to population norms (9.8%).
• Both LGA classifications were associated with the primary outcome and neonatal hyperinsulinemia, but not hypoglycemia or hyperbilirubinemia.
• Predictive ability for most APOs was poor for both customized and population norms (AUC < 0.6 for six of eight APOs).

Conclusions:

• Neither customized nor normalized population fetal growth norms demonstrated superior ability in identifying neonates at risk for APOs related to fetal overgrowth and GDM.
• The predictive performance of both norm types for adverse perinatal outcomes was limited.