Changes in body size of newborns at birth from 1975 to 2005 in China
10.3760/ema.j.issn.1007-9408.2011.11.005
- VernacularTitle:我国初生儿体格发育水平30年变化
- Author:
Yaqin ZHANG
;
Hui LI
- Publication Type:Journal Article
- Keywords:
Infant;
newborn;
Body size;
Body weight
- From:
Chinese Journal of Perinatal Medicine
2011;14(11):660-665
- CountryChina
- Language:Chinese
-
Abstract:
Objective To analyze the changes in body size of Chinese newborns in nine cities during 1975-2005.Methods The data of weight,height and head circumference of newborns within 3 days after birth from four national physical growth surveys named “a national survey on growth of children under seven years of age in nine cities of China” in 1975,1985,1995 and 2005 were used.The investigation areas were urban and suburban areas of Beijing,Harbin and Xi'an in the northern part;Shanghai,Nanjing and Wuhan in the central part; Guangzhou,Fuzhou and Kunming in the southern part of China.Random cluster sampling method was used,7325,6660,7109 and 6144 healthy newborns were examined in 1975,1985,1995 and 2005,respectively.The changes of body size between 1975 and 2005,urban-suburban difference and regional difference were compared with u test,ANOVA or x2 test.Results(1)The average weight had increased during the past 30 years no matter boys and girls,from urban and suburban areas.The increments was 40 ～ 100 g.The percentiles of weight had also increased and the distribution had shifted noticeably towards heavier weights.The proportion of macrosomia had increased from 3.2％(212/6660)in 1985 to 4.3％(265/6144)in 2005.(2)The length of newborns remained unchanged over the 30-year period no matter boys and girls,from urban and suburban areas.Head circumference of newborns showed only a minor increase(0.1～0.3 cm).(3)Ponderal index(PI)had increased gradually from 1975 to 2005.The means of PI had increased from 25.4 kg/m3 in 1975 to 26.0 kg/m3 in 2005.(4)Body size of urban newborns was slightly bigger than that of suburban newborns.The urban-suburban difference of weight and height became smaller and smaller in the 30 years,while the urban-suburban difference in PI became slightly bigger in 2005.(5)Weight,height and head circumference of newborns in northern and central areas were higher than those of southern newborns and the regional difference had not significant changes in the 30 years.The PI of newborns in northern and central areas was higher than that of southern part in 1975,while the PI of southern part became the highest in 2005.Conclusions The body size of newborns became slightly bigger and the proportion of macrosomia increased between 1975 and 2005.The urban-suburban difference became smaller and the regional difference remained in the 30 years.
