Harris Birthright Research Centre for Fetal Medicine and Early Pregnancy Unit, King's College Hospital, London, UK.
Fetal Diagn Ther. 2010;28(4):207-19. doi: 10.1159/000319589. Epub 2010 Sep 18.
To construct normal ranges for embryonic crown-rump length (CRL), heart rate (HR), gestational sac diameter (GSD) and yolk sac diameter (YSD) at 6-10 weeks of gestation.
We examined 4,698 singleton pregnancies with ultrasound measurements of CRL, HR, GSD and YSD at 6-10 weeks and CRL at 11-13 weeks resulting in the live birth after 36 weeks of phenotypically normal neonates with birth weight above the 5th centile. Gestational age was derived from CRL at the 11- to 13-week scan using the formula of Robinson and Fleming. Regression analysis was used to establish normal ranges of CRL, fetal HR, GSD and YSD with gestation, and fetal HR, GSD and YSD with CRL.
At 6-10 weeks there were significant quadratic associations between CRL, GSD, YSD and gestation and between HR, GSD, YSD and CRL, and a cubic association between HR and gestation. The estimated gestation from CRL was the same as that of Robinson and Fleming for a CRL of 10.2-36.5 mm, but the formula of Robinson and Fleming underestimated the gestation by 1 day for a CRL 7.4-10.2 mm and this increased to 9 days for a CRL of 1 mm.
This study established normal ranges for early pregnancy biometry.
构建 6-10 孕周胚胎头臀长（CRL）、心率（HR）、孕囊直径（GSD）和卵黄囊直径（YSD）的正常范围。
我们检查了 4698 例单胎妊娠，这些妊娠在 6-10 孕周时进行了 CRL、HR、GSD 和 YSD 的超声测量，在 11-13 孕周时进行了 CRL 的测量，最终分娩出了表型正常的新生儿，且活产儿在 36 孕周后，出生体重高于第 5 百分位。胎龄是根据 11-13 周超声扫描的 CRL 使用 Robinson 和 Fleming 公式计算得出的。回归分析用于建立 CRL、胎儿 HR、GSD 和 YSD 与孕龄以及胎儿 HR、GSD 和 YSD 与 CRL 的正常范围。
在 6-10 孕周时，CRL、GSD、YSD 与孕龄以及 HR、GSD、YSD 与 CRL 之间存在显著的二次关联，而 HR 与孕龄之间存在三次关联。根据 CRL 估计的孕龄与 Robinson 和 Fleming 公式对于 10.2-36.5mm 的 CRL 是相同的，但 Robinson 和 Fleming 公式对于 7.4-10.2mm 的 CRL 低估了 1 天的孕龄，而对于 1mm 的 CRL，这个低估值增加到了 9 天。
本研究建立了早孕生物测量的正常范围。
