Antenatal Fetal Size and Obesity in Five-Year-Old Children in a Large Cohort Created by Data Linkage

Area of Science:

• Pediatrics
• Obstetrics
• Public Health

Background:

• Childhood obesity is a growing concern with complex developmental origins.
• The specific gestational ages at which fetal growth deviates in children who later develop obesity are not well understood.
• Identifying early predictors of obesity is crucial for timely intervention.

Purpose of the Study:

• To test the hypothesis that large-for-gestational age (LGA) before birth is associated with an increased risk of obesity in early childhood.
• To investigate fetal growth patterns in relation to childhood weight status.

Main Methods:

• Retrospective cohort study utilizing routinely collected antenatal ultrasound data.
• Ultrasound assessments from the first, second, and third trimesters were linked to anthropometric measurements at 5.5 years of age.
• Statistical analysis compared fetal size z-scores across different childhood weight categories (obesity, overweight, healthy weight, thin).

Main Results:

• Children who developed obesity were shorter in the first trimester and heavier in the second and third trimesters compared to healthy-weight children.
• Significant differences in fetal growth trajectories were observed as early as the first trimester.
• Thin children were lighter and overweight children were heavier in the third trimester compared to healthy-weight peers, independent of birth weight.

Conclusions:

• Fetal growth patterns, detectable even in the first trimester, are associated with childhood weight status.
• The distinct growth trajectories for obesity, overweight, and thin children suggest different underlying biological mechanisms.
• Early fetal size may serve as a potential marker for predicting childhood obesity risk.