Development of a New Growth Standard for Breastfed Chinese Infants: What Is the Difference from the WHO Growth Standards?

Abstract

The objectives of this longitudinal study were to examine the trajectory of breastfed infants’ growth in China to update growth standards for early childhood, and to compare these updated Chinese growth standards with the growth standards recommended by the World Health Organization (WHO) in 2006.This longitudinal cohort study enrolled 1,840 healthy breastfed infants living in an "optimal" environment favorable to growth and followed up until one year of age from 2007 to 2010. The study subjects were recruited from 60 communities in twelve cities in China. A participating infant’s birth weight was measured within the first hour of the infant’s life, and birth length and head circumference within 24 hours after birth. Repeated weekly and monthly anthropometric measurements were also taken. Multilevel (ML) modelling via MLwiN2.25 was fitted to estimate the growth curves of weight-for-age (WFA), length-for-age (LFA), and head circumference-for-age (HFA) for the study sample as a whole and by child sex, controlling for mode of delivery, the gravidity and parity of the mother, infant’s physical measurements at birth, infant’s daily food intaking frequency per day, infant’s medical conditions, the season when the infant’s physical measurement was taken, parents’ ages, heights, and attained education, and family structure and income per month. During the first four weeks after birth, breastfed infants showed an increase in weight, length, and head circumference of 1110g, 4.9 cm, and 3.2 cm, respectively, among boys, and 980 g, 4.4 cm, and 2.8 cm, respectively, among girls. Throughout infancy, the total growth for these three was 6930 g, 26.4 cm, and 12.5 cm, respectively, among boys, and 6480 g, 25.5 cm, and 11.7 cm, respectively, among girls. As expected, there was a significant sex difference in growth during the first year. In comparison with the WHO growth standards, breastfed children in our study were heavier in weight, longer in length, and bigger in head circumference, with the exception of a few age points during the first two to four months on the upper two percentile curves.Our data suggested the growth curves for breastfed infants in China were significantly different in comparison with those based on the WHO standards. The adoption of the WHO infant growth standards among Chinese infants, as well as the methods used in the development of such growth standards in China, need careful and coordinated consideration.

Growth patterns from birth to 24 months in Chinese children: a birth cohorts study across China

“…Healthy children in some countries are classified (perhaps inappropriately) as “stunted” [ 16 ]. In opposite of findings from some countries (overestimating stunting) [ 16 ], overall, our study confirmed that the values of growth measures were higher for the key z-score cutoffs in Chinese children in comparison with WHO growth standards [ 3 , 5 ].…”

“…Longitudinal data from a sample with stricter inclusion/exclusion criteria would provide a better comparison to the WHO standards. A small cohort [ 5 ] recruited in 2007 ( n = 1531 retained up to 1 year of age) with strict WHO criteria applied showed significant differences (heavier in weight, longer in length, and bigger in head circumference) compared to WHO standards, as well as compared to the current cross-sectional references, which showed similar differences (except for the 97th percentiles that were lower rather than higher).…”

Comparison of the effects of different growth standards on infants in Urban Shanghai

“…In comparison with the WHO growth standards, breastfed children in that study were heavier in weight, longer in length, and bigger in head circumference, and the results were similar to what we saw in the growth reference of the 2005 nine-city study. [29] In that study and another study, [30] researchers were concerned that there was a possibility to misclassify a few malnourished infants as normal by the infant growth standards based on the WHO MGRS study. Those infants, typically living in rural areas, might subsequently miss the opportunity for early intervention.…”

Differences between WHO Growth Standards and China Growth Standards in Assessing the Nutritional Status of Children Aged 0–36 Months Old

“…Therefore, the WHO working group recommended adding samples from East and South Asia when setting standards. The WHO invited China to join the study, but China declined to participate; thus, there is a lack of samples from East Asia in the 2006 version of the WHO's standards [12].…”

“…In this study, we selected children born in three communities in Kaifu District, Changsha City, Hunan Province, in 2015 as research subjects. The length/height and weight data of children aged 1, 3,6,8,12,18,24, and 36 months were collected prospectively. We used the 2006 edition of the WHO's growth standards and the 2009 edition of China's growth standards to calculate the z-score of each child.…”