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

BackgroundAssessment of child growth is important in detecting under- and over-growth. We aimed to examine the growth patterns of healthy Chinese infants from birth to 24months.MethodsThis study was based on six recent birth cohorts across China, which provided data (from 2015) on 4251 children (2174 boys, 2077 girls) who were born at term to mothers without gestational or preexisting diabetes, chronic hypertension, preeclampsia, or eclampsia. Analyses were performed using 28,298 longitudinal anthropometric measures in 4251 children and the LMS method to generate smoothed Z-score growth curves, which were compared to the WHO growth standards (which are based on data from 2003) and current Chinese growth references (which are based on data from 2005).ResultsMost (80.3%) of mother had college education or more, and maternal smoking was rare (0.4%). Compared to the WHO longitudinal growth standards for children aged 0 to 2years, the growth references from this longitudinal study (length-, weight-, head circumference-, BMI-for-age, and weight-for-length) were significantly higher, for boys and girls; Specifically, the median length-, weight-, head circumference-, BMI-for-age, and weight-for-length was on average 0.9 (range 0.2-1.3) cm, 0.51 (range 0.09-0.74) kg, 0.17 (range-0.24 to 0.37) cm, 0.70 (range 0.01 to 0.92) kg/m(2), and 0.43 (range 0.01 to 1.07) kg higher in Chinese boys, and 1.3 (range 0.5-1.9) cm, 0.73 (range 0.10-0.91) kg, 0.45 (range 0.15-0.62) cm, 0.7 (range 0.0 to 1.0) kg/m(2), and 0.42 (range 0.00 to 0.64) kg greater in Chinese girls, respectively. Compared to the current China cross-sectional growth references (based on data from a decade ago), growth references from this study were also higher, but the difference was less than that between growth references of this study and WHO growth standards.ConclusionsThis recent multicenter prospective birth cohort study examined early growth patterns in China. The new growth curves represent the growth patterns of healthy Chinese infants evaluated longitudinally from 0 to 24months of age, and provide references for monitoring growth in early life in modern China that are more recent than WHO longitudinal growth standards from other countries and previous cross-sectional growth references for China.