Gabbay-Benziv Rinat, Crimmins Sarah, Contag Stephen A
Department of Obstetrics, Gynecology and Reproductive Sciences, University of Maryland School of Medicine, Baltimore, Maryland USA.
Helen Schneider Hospital for Women, Rabin Medical Center, Petach-Tikva, Israel.
J Ultrasound Med. 2017 Apr;36(4):793-798. doi: 10.7863/ultra.16.02049. Epub 2017 Jan 10.
To determine reference values for sonography-based estimated fetal weight (EFW) in twin gestations in one single tertiary medical center in the United States.
A retrospective longitudinal analysis of EFW evaluations of fetuses of twin gestations between November 2006 and June 2016. Fetuses with major congenital anomalies or chromosomal abnormalities were excluded. Estimated fetal weight was calculated using the Hadlock 1985 formula. Linear mixed models were used to allow for multiple but inconsistent observations among individuals, and to account for intertwin differences as well as for gender. Reference values were constructed using a best-fit regression model for estimation of mean and standard deviation at each gestational age after normalization of variables. Chorionicity-specific curves were constructed.
A total of 5515 ultrasound examinations were performed in 2115 twin pregnancies between 24 and 38 weeks of gestation (2.6 ± 4.0 scans/pregnancy). Values corresponding to the 5th, 10th, 50th, 90th, and 95th percentiles for EFW are presented for every gestational age. At 28, 32, and 36 weeks, values were as follows: 855, 1109, and 1363 g; 1351, 1732, and 2294 g; and 1363, 2112, and 2881 g for the 10th, 50th, and 90th percentiles, respectively. Chorionicity-specific curves are presented for comparison with previously published references.
Reference values for sonographic-based fetal growth are presented for clinical and research use.
在美国一家单一的三级医疗中心确定双胎妊娠中基于超声的估计胎儿体重（EFW）的参考值。
对2006年11月至2016年6月期间双胎妊娠胎儿的EFW评估进行回顾性纵向分析。排除有重大先天性异常或染色体异常的胎儿。使用1985年哈德洛克公式计算估计胎儿体重。采用线性混合模型以考虑个体间多个但不一致的观察结果，并考虑双胎间差异以及性别因素。在对变量进行标准化后，使用最佳拟合回归模型构建每个孕周的均值和标准差估计的参考值。构建了绒毛膜性特异性曲线。
在2115例双胎妊娠的24至38孕周期间共进行了5515次超声检查（每次妊娠2.6±4.0次扫描）。给出了每个孕周EFW对应第5、10、50、90和95百分位数的值。在28、32和36周时，第10、50和90百分位数的值分别如下：855、1109和1363克；1351、1732和2294克；以及1363、2112和2881克。给出了绒毛膜性特异性曲线以与先前发表的参考文献进行比较。
给出了基于超声的胎儿生长参考值，供临床和研究使用。
