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Longitudinal growth of head circumference in term symmetric and asymmetric small for gestational age infants
Harvinder Kaur1, A K Bhalla, Praveen Kumar
1Department of Pediatric Medicine, Advanced Pediatrics Centre, Postgraduate Institute of Medical Education & Research, Chandigarh, India.
Insights
Asymmetric small for gestational age (SGA) infants show better head circumference growth in the first year than symmetric SGA infants. This may be due to prenatal "head sparing" effects in asymmetric SGA babies.
Area of Science:
- Pediatric Growth and Development
- Neonatal Nutrition and Metabolism
Background:
- Small for gestational age (SGA) infants exhibit distinct growth trajectories.
- Understanding head circumference (HC) growth is crucial for assessing neurodevelopmental outcomes in SGA infants.
Purpose of the Study:
- To analyze the longitudinal head circumference growth patterns in full-term, symmetric and asymmetric SGA infants compared to appropriate for gestational age (AGA) infants during the first year of life.
- To investigate sex-based differences in HC growth among SGA infants.
Main Methods:
- A mixed-longitudinal study design was employed.
- Head circumference was measured in 300 full-term infants (100 symmetric SGA, 100 asymmetric SGA, 100 AGA) at birth, and at 1, 3, 6, 9, and 12 months.
- Standardized measurement techniques and instruments were utilized.
Main Results:
- SGA infants (both symmetric and asymmetric) had significantly smaller head circumferences than AGA infants throughout the first year.
- Male symmetric SGA infants had significantly smaller HC than asymmetric SGA infants. Female symmetric SGA infants showed smaller HC after 6 months.
- Growth velocity for HC in male SGA infants did not differ significantly between symmetric and asymmetric groups. Female asymmetric SGA infants exhibited faster HC growth between 3-6 months, with a trend reversal later.
Conclusions:
- Asymmetric SGA infants demonstrated superior head circumference growth compared to symmetric SGA infants during the first postnatal year.
- The enhanced growth in asymmetric SGA infants may be linked to the persistence of prenatal "head sparing" mechanisms.
- These findings highlight the importance of considering SGA sub-types for growth monitoring and potential interventions.
Aims:
To study longitudinal growth pattern of head circumference of full-term symmetric and asymmetric small for gestational age (SGA) infants of the two sexes during first year of life.
Study Design:
Mixed-longitudinal growth research design.
Subjects:
Head circumference amongst full-term 100 symmetric, 100 asymmetric as well as 100 appropriate for gestational age (AGA) infants was measured at birth, 1, 3, 6, 9 and 12 months of age using standardized technique and instrument.
Results:
The mean head circumference of male symmetric SGA infants measured significantly (p≤0.001) smaller than asymmetric SGA infants while, in female symmetric SGA infants it measured shorter beyond 6 months. As compared to AGA infants, head circumference in symmetric and asymmetric SGA infants measured significantly smaller in size. Growth velocity for head circumference amongst symmetric and asymmetric SGA male infants did not show statistically significant differences. Rate of head circumference growth remained significantly higher amongst female asymmetric SGA infants than the symmetric ones between 3 and 6 months while, a reversal of trend was observed between 9 and 12 months.
Conclusion:
The better growth attainments for head circumference of male and female asymmetric SGA infants than their symmetric SGA counterparts during first postnatal year of life may be attributed to the continuation of influence of "head sparing" experienced by asymmetric SGA babies during prenatal life.
