小于胎龄儿(SGA)是指出生体质量在同胎龄平均体质量的第10个百分位以下新生儿〔1〕。其出生时体质量、身高都落后于正常新生儿,但生后可出现追赶生长,多在2年内完成,其中大多数在生后6个月内达到同龄儿童正常水平。约87%SGA生后第1个月开始出现追赶生长,约13%的患儿追赶生长不明显,到2岁时身高仍不能实现追赶生长,其达到正常 Smaller than gestational age (SGA) refers to the birth weight in the same gestational age average body mass below the tenth percentile of newborns [1]. The birth weight and height are behind the normal newborn, but after birth may catch up with growth, mostly completed within 2 years, most of them within 6 months after birth to reach the normal level of children of the same age. About 87% of SGA started catch-up growth in the first month of life, and about 13% of children did not catch up with growth until the age of 2, and they still could not catch up with growth until they reached normal