Fetal Medicine Unit, Department of Obstetrics and Gynecology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR.
Ultrasound Obstet Gynecol. 2009 Sep;34(3):283-7. doi: 10.1002/uog.6455.
To investigate which ultrasound or biochemical markers in both the first and the second trimesters are the best predictors for fetal growth and small-for-gestational age (SGA).
This was a prospective study of 619 Chinese women with a singleton pregnancy. At 11 to 13 + 6 weeks, fetal crown-rump length (CRL), placental volume (PlaV), uterine artery pulsatility index (UtA-PI), and the maternal serum levels of pregnancy-associated plasma protein-A (PAPP-A) and free beta-human chorionic gonadotropin (beta-hCG) were measured. Fetal biparietal diameter, femur length, abdominal and head circumference, PlaV and UtA-PI were then measured at 18-22 weeks. All markers were transformed to gestational age-specific Z-scores or multiples of the median (MoM). Birth weights were also transformed to Z-scores using the individualized gestational age-related optimal weight based on a locally derived nomogram. The relationship between all markers and the customized birth weight were examined, and their predictive powers for SGA were examined by regression analysis.
Univariate analysis revealed that all markers except free beta-hCG correlated with birth weight Z-score. After multiple linear regression analysis, only PlaV, UtA-PI and CRL in the first trimester, and PlaV and UtA-PI in the second trimester, stood out as independent markers. Logistic regression analysis showed that PlaV was the only independent first-trimester predictor of SGA, and in the second trimester both PlaV and UtA-PI were independent predictors. The sensitivity of these first- and second-trimester markers in predicting SGA were 41% and 45%, respectively, at a false-positive rate of 20%. Combining them did not significantly improve prediction of SGA.
Among the various known ultrasound and biochemical markers, only the first-trimester PlaV and the second-trimester PlaV plus UtA-PI are independent predictors for SGA.
研究头臀长（CRL）、胎盘体积（PlaV）、子宫动脉搏动指数（UtA-PI）、妊娠相关血浆蛋白 A（PAPP-A）和游离β-人绒毛膜促性腺激素（β-hCG）在早孕期，以及双顶径、股骨长、腹围、头围、PlaV 和 UtA-PI 在中孕期的超声和生化标志物中，哪些是预测胎儿生长和小于胎龄儿（SGA）的最佳指标。
这是一项前瞻性研究，纳入了 619 例单胎妊娠的中国妇女。在 11 至 13+6 周时，测量胎儿的 CRL、PlaV、UtA-PI 以及孕妇血清中的 PAPP-A 和游离β-hCG 水平。在 18-22 周时测量胎儿的双顶径、股骨长、腹围、头围、PlaV 和 UtA-PI。所有标志物均转化为与胎龄相关的 Z 评分或中位数倍数（MoM）。出生体重也使用基于本地衍生的列线图的个体化胎龄相关最佳体重进行 Z 评分转换。检查所有标志物与定制出生体重之间的关系，并通过回归分析检查其对 SGA 的预测能力。
单因素分析显示，除游离β-hCG 外，所有标志物均与出生体重 Z 评分相关。多元线性回归分析后，仅早孕期的 PlaV、UtA-PI 和 CRL，以及中孕期的 PlaV 和 UtA-PI 为独立标志物。Logistic 回归分析显示，PlaV 是 SGA 的唯一独立早孕期预测指标，而中孕期 PlaV 和 UtA-PI 均为独立预测指标。这些早、中孕期标志物预测 SGA 的灵敏度分别为 41%和 45%，假阳性率为 20%。联合使用这些标志物并不能显著提高 SGA 的预测能力。
在已知的各种超声和生化标志物中，只有早孕期的 PlaV 和中孕期的 PlaV 加 UtA-PI 是 SGA 的独立预测指标。
