[A longitudinal study of growth of breast fed infants in rural areas of six economically better developed provinces in China].

OBJECTIVE

To understand growth pattern of breast-fed infants in rural areas and provide relevant reference data.

METHOD

In 30 towns of economically better developed rural regions of six provinces in China, 1058 subjects were recruited by the project, and their weight, length, and head circumference were measured longitudinally from birth to 12 months of age. The monitoring frequency was 16 times in total. Among these samples, 764 cases met the breast-fed infants definition by WHO. Statistical analysis was performed using SAS and SPSS software.

RESULT

In the first month after birth, the increment per week of breast-fed infants' weight gain has gradually accelerated, while length and head circumference showed a uniform rate. The three indicators in the neonatal period, respectively, attained an increase of about 980 g, 4.4 cm and 2.9 cm. Monthly increment of infant weight gain reached a peak at 2 months old, and then gradually declined. The remaining two indicators continued to decline. During the first year after birth, the infants' weight, length, and head circumference increased by 6.2 - 6.6 kg, 24.8 - 25.3 cm and 11.4 - 11.9 cm respectively. Compared to WHO 2006 new growth standard, rural breastfed infant weight was about 80 - 510 g higher, but not in neonatal period. For length, boys' average values were about 0.2 - 0.5 cm lower than WHO standard in most of the month groups, while girls' values were slightly higher.

CONCLUSION

The growth potential of rural breast fed infants in China reached WHO 2006 new standard. This study provided reference data for breast-fed infants' growth in rural areas.