Growth of Breast-fed and Formula-fed Infants Compared with National Growth References of Thai Children
Supapan Tantracheewathorn, MD*
Affiliation : * Department of Pediatrics, Bangkok Metropolitan Administration Medical College and Vajira Hospital
Objective : To compare the growth patterns of breast-fed (BF) and formula-fed (FF) infants with national
growth references of Thai children and to determine whether the Thai growth references can be used to assess
growth of BF infants who were fed according to Thai guidelines of infant feeding.
Design : Cohort study
Materials and Methods : One hundred and fifty six term infants (78 BF and 78 FF infants) were followed
prospectively for 12 months. Milk was the only food source during the first 4 months and solid foods were
introduced after 4 months of age. Body weight, length and head circumference were measured at the age of
1, 2, 4, 6, 9 and 12 months.
Results : Of the 156 infants, 140 completed the study (71 BF and 69 FF infants). BF and FF infants had
similar mean weight and length from 0 to 6 months, thereafter BF infants had lower weight and length than
FF infants with significant difference at 9-12 months in male infants and at 12 months in female infants (p <
0.05). Compared with national growth references of Thai children, mean weight and length of BF and FF
infants in the study were significantly lower than the mean values of Thai infants from 0 to 1 months,
thereafter mean weight and length of BF infants were close to the Thai references but those of FF infants were
higher than the Thai references after 6 months with significant difference in weight from 9 to 12 months and
length at 12 months. The incidence of malnutrition and obesity at 1 year of age was not different between the
two feeding groups. Inadequate complementary food was the risk factor of infant malnutrition (adjusted RR
4.7, 95%CI 1.1-21.9, p 0.04).
Conclusion : BF and FF infants had similar weight and length from birth to 6 months, thereafter, FF infants
had higher weight and length than BF infants and Thai growth references. Growth of BF infants correlated
well with the national growth references of Thai children, so the Thai growth references can be used to assess
growth of BF infants who were fed according to Thai guidelines of infant feeding.
Keywords : Breastfeeding, Formula feeding, Growth, Infant
