Birth anthropometry among three Asian racial groups in Singapore: proposed new growth charts

OBJECTIVE: We analysed birth anthropometry of babies of Chinese, Malay and Indian ancestry living in Singapore with an aim to develop gestational age (GA) and gender-specific birth anthropometry charts and compare these with the widely used Fenton charts. DESIGN: Retrospective observational study. SETTING: Department of Neonatology, National University Hospital, Singapore. POPULATION: We report data from 52 220 infants, born between 1991–1997 and 2010–2017 in Singapore. METHODS: Anthropometry charts were built using smoothened centile curves and compared with Fenton’s using binomial test. Birth weight (BW), crown-heel length and head circumference (HC) were each modelled with maternal exposures using general additive model. MAIN OUTCOME MEASURES: BW, crown-heel length and HC. RESULTS: There were 22 248 Chinese (43%), 16 006 Malay (31%) and 8543 Indian (16%) babies. Mean BW was 3103 g (95% CI 3096 to 3109), 3075 g (95% CI 3067 to 3083) and 3052 g (95% CI 3041 to 3062) for Chinese, Malays and Indians, respectively. When exposed to a uniform socioeconomic environment, intrauterine growth and birth anthropometry of studied races were almost identical. From our GA-specific anthropometric charts until about late prematurity, Asian growth curves mirrored that of Fenton’s; thereafter, Asian babies showed a reduction in growth velocity. CONCLUSIONS: These findings suggest that Asian babies living in relatively uniform socioeconomic strata exhibit similar growth patterns. There is a slowing of growth among Asian babies towards term, prompting review of existing birth anthropometry charts. The proposed charts will increase accuracy of identification of true fetal growth restriction as well as true postnatal growth failure in preterm infants when applied to the appropriate population.