产前部分上臂容积测量与新生儿出生体质量的相关性

目的探讨三维超声5D Limb技术测量正常孕晚期临产前7 d内胎儿部分上臂容积（AVol）在新生儿估算出生体质量（EFW）中的应用价值。 方法选取2018年7月至2019年6月期间在苏州市吴中人民医院超声科进行产检的临产前7 d内的115例胎儿作为研究对象，运用二维、三维超声技术为孕妇产检，并记录相关测量值，主要包括双顶径、股骨长度、头围、腹围、AVol。采用单因素和多因素线性回归分析各参数与新生儿BW之间的相关性，并建立回归方程产生新的BW估算公式。以新生儿BW为金标准，Hadlock经典公式为对照，运用χ²检验比较Hadlock经典公式与新公式的估算符合率（绝对误差和相对误差）的差异。再将胎儿按照BW分为低BW组、正常BW组和巨大儿组，运用配对t检验比较2种公式估算3组胎儿BW的相对误差（系统误差±随机误差）的差异。 结果单因素相关分析显示，BW与双顶径、头围、腹围、股骨长度、AVol均具有相关性（r=0.477、0.515、0.506、0.404、0.827，P均＜0.001）；多因素回归分析显示，腹围、AVol为新生儿BW估算的独立影响因素（P=0.007、＜0.001）；基于双顶径、头围、腹围、股骨长度、AVol构建回归方程EFW（AVol）=-2470.985+56.547×双顶径+33.225×头围+50.142×腹围+169.806×股骨+47.203×AVol。EFW（AVol）公式估算BW的绝对误差符合率和相对误差符合率均高于Hadlock经典公式（65.2% vs 48.7%；84.3% vs 64.3%），差异具有统计学意义（P=0.011、＜0.001）。EFW（AVol）公式和Hadlock经典公式估算低BW组、正常BW组和巨大儿组胎儿BW的相对误差分别为（19.5%±7.2% vs 44.8%±29.6%）、（5.5%±4.3% vs 7.8%±5.5%）、（5.3%±3.4% vs 8.5%±4.5%），2种公式对正常BW组胎儿BW估算的相对误差比较，差异具有统计学意义（P＜0.001）。 结论AVol与BW相关性显著，可作为新参数应用于估算新生儿BW的临床实践中。

Correlation between prenatal fractional upper arm volume and neonatal birth weight

ObjectiveTo explore the application value of fetal fractional upper arm volume (AVol) measured by three-dimensional ultrasound 5D Limb technique within 7 days before delivery in the normal third trimester of pregnancy in neonatal birth weight (BW) estimation. MethodsFrom July 2018 to June 2019, 115 fetuses within 7 days before delivery at the Ultrasound Department of Wuzhong People's Hospital in Suzhou City were selected as the research subjects. Two-dimensional and three-dimensional ultrasound technology was used for maternity examination. The measured values mainly included double parietal diameter (BPD), femoral length (FL), head circumference (HC), abdominal circumference (AC), and AVol. The correlations between each parameter and newborn BW were analyzed and a multi-factor linear regression equation was established to generate a new weight estimation formula. With BW as the gold standard and Hadlock classic formula as a control, the Chi-square test was used to analyze the absolute error and relative error coincidence rate of the new formula. Then, the fetuses were divided into a low BW group, a normal BW group, and a macrosomia group according to BW. Paired t-test was used to estimate the systematic and random errors of BW of different groups of fetuses. ResultsBW had significant correlations with BPD, HC, AC, FL, and AVol (r=0.477, P＜0.001; r=0.515, P＜0.001; r=0.506, P＜0.001; r=0.404, P＜0.001; r=0.827, P＜0.001). The regression equation generated was EFW(AVol)=-2470.985+56.547×BPD+33.225×HC+50.142×AC+169.806×FL+47.203×AVol. The new formula had significantly higher absolute and relative error compliance rates for BW estimation than the Hadlock classical formula (65.2% vs 48.7%, P=0.011; 84.3% vs 64.3%, P＜0.001). The relative errors of the new formula and the Hadlock classical formula for fetal BW estimation in the low BW group, normal BW group, and macrosomia group were (19.5%±7.2%) vs (44.8%±29.6%), (5.5%±4.3%) vs (7.8%±5.5%), and (5.3%±3.4%) vs (8.5%±4.4%), respectively, with statistically significant differences between the two formulas (P＜0.001). ConclusionAVol has a significant correlation with BW, and can be used as a new parameter for estimating neonatal BW in clinical practice.