关于婴儿生长受损预后不良的概念仅在近25年内连续观察才有了进展。17世纪末和18世纪著名的产科医生法国 Mauriceau和英国 Snellie 估计出生体重为15～16磅。1961年 WHO 在母婴健康专家委员会上仅将婴儿体重少于2,500g 定为低体重,未提及孕龄。低出生体重儿可分三类:(1)新生儿体重符合孕龄,孕37周前分娩的为早产新生儿;(2)新生儿体重小于孕龄,孕37周前分娩的为早产生长迟缓新生儿;(3)新生儿体重小于孕龄,孕37周后分娩的为足月生长迟缓新生儿,占所有低体重儿的33%。迄今宫内生长迟缓新生儿最普通的定义是婴儿体重低于2,500g,孕龄低于第十百分位,约占分 The notion of a poor prognosis for impaired infant growth has progressed only in the last 25 years. Mauriceau, a famous obstetrician of France in the late 17th and 18th centuries, and Snellie of the United Kingdom have estimated birth weights of 15-16 pounds. 1961 WHO at the Maternal and Child Health Expert Committee will only weigh less than 2,500 g of infant weight, without reference to gestational age. Low birth weight children can be divided into three categories: (1) Neonatal weight in line with gestational age, 37 weeks before delivery for premature birth of newborns; (2) newborn weight less than gestational age, 37 weeks before delivery for premature delivery delay Newborns; (3) Neonatal weight less than gestational age, 37 weeks after delivery of labor for the full-term growth retardation of newborns, accounting for 33% of all children with low birth weight. So far the most common definition of intrauterine growth retardation of newborn babies weighing less than 2,500 g, gestational age below the tenth percentile, accounting for about