Undernutrition and growth restriction in pregnancy

Area of Science:

• Perinatology
• Developmental Biology
• Metabolic Health

Background:

• Newborn size is determined by intrauterine growth, with conditions like prematurity, low birthweight, small for gestational age (SGA), and intrauterine growth restriction (IUGR) resulting in similar weights.
• SGA newborns exhibit reduced lean and fat mass. Etiologies differ globally, with cigarette smoking prevalent in developed nations and food deprivation in developing ones.
• Serial fetal biometry, crucial for diagnosing and assessing intrauterine growth restriction (IUGR), is not yet standard in epidemiological research.

Purpose of the Study:

• To explore the long-term body composition and health outcomes of newborns experiencing restricted intrauterine growth.
• To investigate the relationship between birthweight, catch-up growth, and the development of metabolic syndrome in SGA infants.
• To provide a framework for understanding the programming of regulatory systems by intrauterine malnutrition.

Main Methods:

• Review of follow-up studies on SGA newborns.
• Analysis of associations between birthweight and later body composition (lean mass and adiposity).
• Consideration of theoretical models like the thrifty phenotype and predictive adaptive response.

Main Results:

• A consistent positive association was observed between birthweight and later lean body mass in SGA infants.
• Catch-up growth in length/height is common in SGA infants, often accompanied by increased bodyweight and central adiposity.
• Signs of metabolic syndrome were associated with catch-up growth and central adiposity in these infants.

Conclusions:

• Intrauterine growth restriction and SGA have lasting impacts on body composition and metabolic health.
• Catch-up growth following SGA may program individuals for metabolic syndrome.
• The thrifty phenotype and predictive adaptive response models offer valuable insights into the long-term consequences of intrauterine malnutrition.