高原缺氧环境对世居藏族和移居汉族胎儿生长发育的影响

目的:通过比较高原世居藏族产妇与移居汉族产妇胎盘重量、新生儿体重和胎盘系数,了解高原环境对世居藏族和移居汉族胎儿生长发育的影响。方法:收集、检测和比较生活在海拔3480m高原的世居藏族和移居汉族初产妇分娩的胎盘重量、新生儿体重及胎盘系数,并与平原汉族新生儿出生体重比较;比较移居高原汉族初产妇和经产妇分娩的胎盘重量、新生儿体重及胎盘系数。结果:移居汉族初产妇新生儿低体重出生率显著高于世居藏族(P<0.01);世居藏族初产妇胎盘重量与移居汉族初产妇无显著差别(P>0.05)、新生儿体重高于汉族,差异有显著性(P<0.01);移居汉族初产妇胎盘系数显著高于世居藏族(P<0.05)。移居汉族初产妇胎盘重量和胎盘系数显著高于移居汉族经产妇(P<0.01),二者新生儿出生体重差别无显著性(P>0.05);藏族新生儿体重与平原汉族新生儿出生体重无显著差别(P>0.05);结论:移居汉族产妇,尤其是初产妇,在高原分娩的新生儿体重低于世居藏族和平原汉族,胎盘系数显著高于世居藏族,说明高原环境影响移居汉族胎儿宫内的生长发育。因此,有必要进一步探索高原环境对移居汉族胎儿生长发育的影响机制,以利于加强移居者围产期保健,降低高原缺氧环境对移居者胎儿生长发育的不良影响。

Effects of high altitude on growth and development of immigrant Han fetus

Objective:To explore the effects of hypoxic environment at high altitude on growth and development of native Tibetan and immigrant Han fetus.Methods:Primipara volunteers were divided into three groups: (1) high altitude native Tibetan group(HT group, n=344); (2) high altitude immigrant Han group(HH group, n=77); (3) plain Han group(PH group). The age and gestation status among groups were perfectly matched. Both high altitude groups lived and delivered at high altitude(above sea level 3480 m), and the PH group did in Chongqing(above sea level 300 m). Their neonate birth weight, placental weight and placental ratio were measured.Results:The percentage of low birth weight as well as placental ratio was lower and birth weight was higher in HT group than those in HH group(P<0.05). The neonate birth weight of HT group was similar to that of PH group. No marked difference of placental weight was found between HT group and HH group. The placental weight and placental ratio of HH group were higher than those of PH group(P<0.01), but there was not significantly difference of the neonate birth weight between immigrant Han primipara and multipara(P>0.05).Conclusion:Neonate birth weight of HH group is lower than that either HT group or PH group, which suggested that the hypoxic environment of high altitude may delay intrauterine growth of fetus of immigrant Han pregnant women, but not of native Tibetan pregnant women. The adaptive mechanism of native Tibetans remains to be elucidated.