陕西省育龄妇女围孕期增补叶酸对新生儿出生体重的影响

目的 探讨陕西省育龄妇女围孕期增补叶酸对新生儿出生体重的影响。方法 采用分层多阶段随机抽样方法，以问卷调查方式收集2010-2013年陕西省怀孕且结局明确的育龄妇女及其子女的相关信息。将新生儿出生体重和母亲围孕期是否增补叶酸分别以因变量和自变量纳入多重线性回归及分位数回归模型，并控制相关混杂因素。结果 多重线性回归结果显示，围孕期增补叶酸者子女的出生体重高于未增补者，平均提高29.56 g（B=29.56，t=4.69，P<0.01）。分位数回归结果显示，当新生儿出生体重处于q=0～0.55、q=0.65、q=0.75～0.80百分位点时，增补过叶酸的母亲所生育子女的出生体重高于未增补者，差异有统计学意义，且体重提高的幅度不一致，随着出生体重百分位点的增高，增补过叶酸的母亲所生育子女的出生体重与未增补者相比提高幅度逐渐减小。结论 围孕期增补叶酸可以提高新生儿出生体重，对体重较轻的新生儿影响更大，体重较重的新生儿影响较小甚至无影响。

Effect of folic acid supplementation in childbearing aged women during pregnancy on neonate birth weight in Shaanxi province

Objective To investigate the effect of folic acid supplementation in childbearing aged women during pregnancy on the birth weight of newborns in Shaanxi province. Methods A questionnaire survey was conducted among the childbearing aged women selected through multistage stratified random sampling in Shaanxi during 2010-2013, all of these childbearing aged women were in pregnancy or had definite pregnancy outcomes. The birth weight of newborns and folic acid supplementation during pregnancy were used as the dependent variables and independent variables respectively in multiple linear regression model and quantile regression model and confounding factors were controlled. Results Multiple linear regression analysis showed that the birth weight of newborns whose mothers had folic acid supplementation during pregnancy were significantly higher than those whose mothers had no folic acid supplementation during pregnancy, an average increase of 29.56 g (B=29.56, t=4.69 and P<0.01). Quantile regression analysis showed from very low to higher percentiles (q=0-0.55, q=0.65, q=0.75-0.80), the birth weights of newborns whose mothers supplemented folic acid were higher than those whose mother did not supplement folic acid, the difference was significant, but the increase varied. As the increase of the percentiles of birth weight, the body weight increase declined gradually in those whose mothers had folic acid supplementation compared with those whose mothers had no folic acid supplementation. Conclusion Folic acid supplementation during pregnancy can increase the birth weight of newborns, the influence was greater in newborns with lower body weight than in newborns with higher body weight.