Exploring Infant Size and Body Composition at 18 Months: An Ambidirectional Peri-Urban South African Cohort Study

Area of Science:

• Pediatrics
• Public Health
• Human Growth and Development

Background:

• The first 1000 days of life are critical for establishing foundational growth.
• Understanding factors influencing infant body size and composition is crucial for long-term health outcomes.
• Infant development is influenced by a complex interplay of prenatal, perinatal, and postnatal factors.

Purpose of the Study:

• To identify prenatal, perinatal, and postnatal exposures affecting infant body size and composition at 18 months.
• To analyze the impact of placental function, maternal HIV status, and food insecurity on infant growth metrics.
• To provide insights into factors contributing to stunting and other growth-related issues in early childhood.

Main Methods:

• An ambidirectional study design was employed, tracking infants from birth to 18 months.
• Multiple regression analyses were used to assess associations between exposure variables and infant outcomes.
• Key exposure variables included maternal factors, placental function (umbilical artery resistance index Z-score), and infant feeding practices.

Main Results:

• Higher umbilical artery resistance index Z-score (indicating poorer placental function) was associated with lower birthweight and reduced infant length at 18 months.
• Maternal HIV infection was linked to a reduced length-for-age Z-score at 18 months.
• Household food insecurity predicted reduced fat-free mass-for-age Z-score at 18 months.

Conclusions:

• Infant anthropometry and body composition are significantly influenced by prenatal and postnatal nutrition-related factors.
• Placental insufficiency and household food insecurity have long-term consequences for child development, including stunting.
• Addressing these factors is vital for improving individual health, future generations, and societal well-being.