Accurate assessment of gestational age (GA) is important at both individual and population levels. The most accurate way to estimate GA in women who book late in pregnancy is unknown. The aim of this study was to externally validate the accuracy of equations for GA estimation in late pregnancy and to identify the best equation for estimating GA in women who do not receive an ultrasound scan until the second or third trimester.

中文翻译：

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使用超声估计妊娠中期和晚期胎龄的模型外部验证：一项前瞻性多中心观察性研究


准确评估胎龄 （GA） 在个体和人群层面都很重要。估计妊娠晚期预订的女性 GA 的最准确方法是未知的。本研究的目的是从外部验证妊娠晚期 GA 估计方程的准确性，并确定估计 GA 的最佳方程式，这些方程式直到妊娠中期或晚期才接受超声扫描。