新生儿出生体重预测及相关因素分析

目的分析孕妇产前检查各参数与新生儿出生体重的关系,并推导出预测体重公式。方法随机选取2002-01～2003-02在我院分娩的1012例单胎头位初产妇资料进行回顾性分析,参数选择:产前初检时体重指数(BMI1),孕期增长体重(GWG),临产前1周内体重指数(BMI2)、宫高(UFH)、腹围(AP)及胎儿B型超声检查双顶径(BPD)、头围(HC)、腹围(AC)、股骨长度(FL)、羊水量(AFI)),上述参数与出生后新生儿体重作单元及多元逐步回归分析,推导出预测胎儿体重公式。将2003-04～06符合同样标准的215例孕妇前瞻性验证预测公式的准确性。结果与新生儿出生体重明显相关的因素是AC(r=0.673)、BPD(r=0.602)、HC(r=0.541)、UFH(r=0.518)以及FL(r=0.502)。预测体重公式=69.392×AC+316.883×BPD+41.045×HC+53.070×UFH+334.121×FL-7230.494(r=0.825,P=0.000),预测值的平均绝对误差为186.5±124.9g,平均相对误差为(5.8±4.0)%,符合率80.5%。结论AC是新生儿出生体重的主要相关因素,结合孕妇与胎儿检查参数多元逐步回归分析对新生儿出生体重预测有临床意义。

Analysis of correlative factors and prediction for fetal birth weight

Objective To analyse the relationship between parameters of gravida and fetal birth weight,and derive the formula of estimated fetal weight(EFW). Methods Nulliparas(n=1 012) who had singleton and cephalic presentation were included in a retrospective cohort analysis. Maternal parameters(body mass index(BMI),gestational weight gain(GWG),uterine fundus height(UFH),abdominal perimeter(AP)) and ultrasonographic parameters(fetal biparietal diameter(BPD),head circumference(HC),abdominal circumference(AC),femur length(FL),amniotic fluid index(AFI)) were studied as predictors of EFW,the data on these parameters were analyzed with statistical methods,the coefficients of simple and multiple linear stepwise correlation were analyzed and formulas were established.The new formulas were verified for accuracy of prediction of actual birth weight on 215 cases. Results Significant relative factors of term birth weight were AC(r=0.673),BPD(r=0.602),HC (r=0.541),UFH(r=0.518),FL(r=0.502). Birth weight prediction equation isbirth weight(g)=69.392×AC+316.883×BPD+41.045×HC+53.070×UFH+334.121×FL-7230.494(r=0.825,P=0.000).The average absolute error was (186.5±124.9)g,the average relative error was (5.8±4.0)%,with an agreement rate of 80.5%.Conclusions There is significant correlation between AC and EFW,term birth weight can be accurately predicted using multivariate step-step regression analysis of routine maternal and ultrasound parameters.