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Growth and proportionality in early childhood. I. Within population variations

M Ounsted, V A Moar, A Scott

    Early Human Development
    |February 1, 1986
    PubMed

    Insights

    Postnatal growth in small-for-gestational age (SGA) and large-for-gestational age (LGA) children shows distinct patterns in body proportionality over seven years. These differences highlight variations in head and chest measurements, impacting assessments of child development.

    Area of Science:

    • Pediatrics
    • Human Growth and Development
    • Biometry

    Background:

    • Small-for-gestational age (SGA) and large-for-gestational age (LGA) infants exhibit distinct birth characteristics.
    • Postnatal growth patterns and body proportionality are crucial indicators of child development.
    • Understanding long-term growth trajectories in relation to birth weight is essential for pediatric health.

    Purpose of the Study:

    • To compare postnatal growth patterns and body proportionality in small-for-gestational age (SGA) and large-for-gestational age (LGA) children.
    • To analyze changes in head-chest, head-length, and chest-length ratios over the first seven years of life.
    • To investigate the influence of birth weight group and sex on these proportionality indices.

    Main Methods:

    • Longitudinal study tracking 238 SGA and 241 LGA infants over 7 years.
    • Measurement of three key proportionality ratios: head-chest, head-length, and chest-length.
    • Comparison with a control group of 284 children from the same population.

    Main Results:

    • Significant differences in head-chest and head-length ratios at birth between SGA and LGA groups (P < 0.001).
    • Proportionality ratios showed distinct patterns of change over time, influenced by birth weight and sex.
    • At 7 years, SGA children had higher head-chest/stature ratios, and LGA children had lower ratios, with significant sex differences in girls (P < 0.01).

    Conclusions:

    • Birth weight category significantly impacts long-term body proportionality in children.
    • Sex influences growth patterns within birth weight groups, particularly evident in head measurements.
    • The common criterion for identifying malnutrition based on head and chest circumference crossing by 12 months requires cautious application.

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