早产与足月小于胎龄儿第1年体格生长差异的队列研究

目的 探讨早产小于胎龄儿(small for gestational age,SGA)在生后1年内的体格生长变化趋势是否与足月SGA存在差异,为早产SGA生后体格生长随访监测提供参考依据.方法 采用前瞻性队列研究,收集2013年9月至2015年6月在重庆医科大学附属儿童医院儿童保健科随访的早产SGA 54人,足月SGA 181人.分别在1、3、6、12月龄(早产SGA在纠正胎龄的1、3、6、12月龄)测量体质量、身长、头围,采用Z积分计算体格水平和生长速度.结果 ①早产SGA生后快速追赶生长发生在纠正年龄1月龄后,而足月SGA在生后即开始;早产和足月SGA在前6个月追赶生长率均达63.0％.②早产SGA未纠正胎龄的体质量Z值在6、12月龄(t=-1.189、-0.911,P=0.236、0.363),身长、头围Z值在12月龄(t=-0.855、-1.078,P=0.394、0.282)与足月SGA比较差异无统计学意义.③早产SGA的体质量增长速度在1～3、＞3～6月龄(t=4.685、3.787,P＜0.01),身长、头围在1～3、＞3～6、＞6～ 12月龄追赶速度明显快于足月SGA(t=3.487、3.626、4.179,t=5.158、3.001、4.641,P＜o.o1).但在1月龄内体质量、身长追赶速度均慢于足月SGA(t=-6.384、-4.821,P＜0.01),甚至低于出生时Z值水平(△Z＜0).结论 早产SGA追赶生长的发生晚于足月SGA,体格生长水平可在1岁时追赶上足月SGA,在1岁内生长潜力大于足月SGA,在纠正年龄1月龄内易发生宫外生长迟缓.

Cohort study of physical growth differences between preterm and full-term small for gestational age infants in the first year

Objective To explore the differences of physical growth trends between preterm and fullterm small for gestational age (SGA) infants in the first year.Methods Prospective cohort study was adopted to collect 54 preterm SGA infants and 181 full-term SGA infants,who were followed-up at health care department of children's hospital of Chongqing medical university from September 2013 to June 2015.The weight,length,head circumference and growth rate were measured by using Z scores at the ages of 1 month,3 months,6 months and 12 months,and the preterm SGA infants were measured at the corrected gestational ages of 1 month,3 months,6 months and 12 months.Results Preterm SGA began rapid catch-up growth after corrected age of 1 month,while full-term SGA began after birth.The catch-up growth rates of preterm and full-term SGA reached to 63％ in the first 6 months.There were no significant differences in the weight Z score at the not-corrected gestational age of 6 months and 12 months (t =-1.189,-0.911,P =0.236,0.363),length (t =-0.855,P =0.394) and head circumference Z score in 12 months (t =-1.078,P =0.282) between the preterm SGA infants and full-term SGA infants.The chasing speed of weight (t =4.685,3.787,P ＜ 0.01) of preterm SGA was obviously faster than that of full-term SGA during 1 ～ 3 months and ＞3～6months,and the chasing speeds of length (t =3.487,3.626,4.179,P ＜0.01) and head circumference (t =5.158,3.001,4.641,P ＜ 0.01) in preterm SGA were obviously faster than those of fullterm SGA during 1 ～ 3 months,＞ 3 ～ 6 months and ＞ 6 ～ 12 months.But the chasing speeds of weight and length of preterm SGA were obviously slower than those of full-term SGA within 1 month (t =-6.384,-4.821,P ＜ 0.01),even below the Z score at birth (AZ ＜ 0).Conclusion The starting point of catch-up growth of preterm SGA is latter than that of full-term SGA.The physical growth levels of preterm SGA can catch up with full-term SGA at the age of 1 year old.The growth potential of preterm SGA is greater than that of full-term SGA.Extrauterine growth retardation is easier to happen in preterm SGA infants at the corrected age of 1 month.