Population-based intrauterine growth curves from computerized birth certificates

Area of Science:

• Perinatology
• Neonatal screening
• Biostatistics

Background:

• Standard newborn screening practices often utilize growth curves derived from dissimilar populations, leading to significant diagnostic errors.
• Accurate assessment of fetal growth and newborn size relative to gestational age is critical for identifying potential health risks.

Purpose of the Study:

• To develop accurate, population-specific intrauterine growth curves for birth weight based on gestational age.
• To improve the reliability of newborn screening by using locally relevant growth data.

Main Methods:

• Utilized North Carolina's computerized birth certificate file for data analysis.
• Developed a novel technique to construct percentile curves for birth weight across different gestational ages, minimizing erroneous gestational age data.
• Compared newly derived North Carolina-specific curves with existing growth curves (e.g., Colorado curve).

Main Results:

• The developed intrauterine growth curves reflect birth weights specific to North Carolina newborns.
• These new curves show higher birth weights than low-income subpopulations but lower than populations with superior living standards and prenatal care.
• Application of the Colorado intrauterine growth curve to North Carolina births resulted in significant overdiagnosis of 'large for gestational age' infants and underdiagnosis of 'small for gestational age' infants.

Conclusions:

• Population-specific intrauterine growth curves are essential for accurate newborn screening and diagnosis.
• The developed North Carolina-specific curves provide a more accurate reference for assessing fetal growth and birth weight in this population.
• Utilizing inappropriate growth curves can lead to misclassification of newborns, potentially delaying necessary interventions.