Socioeconomic determinants of infant growth: The Perspective Cohort Study of Thai Children.

Aim:   The present study is based on the Prospective Cohort Study of Thai Children (PCTC), and focuses on socioeconomic factors including maternal age, maternal education, living with parents, family size, family income, locality, and sex that affect the growth outcomes of infants at 1 year of age.

Methods:   Data was collected among 3679 pairs of mothers and infants in the PCTC cohort in rural and urban locations during 2001-2002. Data collection was performed by interviewing mothers in their 7th to 8th month of pregnancy using family profile questionnaires. The anthropometric measures including weight, length, and head circumference of the infants were later collected at 1 year of age at home.

Results:   The results show the effects of family socioeconomic status maternal education, living with parents, family size, family income, locality, and sex on their weight (R(2) = 14.2%, P < 0.001) and length (R(2) = 8.7%, P < 0.001) at 1 year of age. The findings suggest that maternal age, maternal education, living with parents, family size, family income, locality, and sex predict infant head circumference (R(2) = 16.8%, P < 0.001) at 1 year of age.

Conclusion:   Infants' growth, including weight, height, and head circumference, are affected by family socioeconomic status factors. It is recommended that the effect of maternal age on growth and development of children among those in the PCTC cohort is examined in the future.