Barcelona Center for Maternal-Fetal and Neonatal Medicine (Hospital Clínic and Hospital Sant Joan de Deu), Institut d'Investigacions Biomèdiques August Pi i Sunyer, University of Barcelona; and Center for Biomedical Research on Rare Diseases, Madrid, Spain.
Barcelona Center for Maternal-Fetal and Neonatal Medicine (Hospital Clínic and Hospital Sant Joan de Deu), Institut d'Investigacions Biomèdiques August Pi i Sunyer, University of Barcelona; and Center for Biomedical Research on Rare Diseases, Madrid, Spain.
Am J Obstet Gynecol. 2018 Feb;218(2S):S790-S802.e1. doi: 10.1016/j.ajog.2017.12.003.
By consensus, late fetal growth restriction is that diagnosed >32 weeks. This condition is mildly associated with a higher risk of perinatal hypoxic events and suboptimal neurodevelopment. Histologically, it is characterized by the presence of uteroplacental vascular lesions (especially infarcts), although the incidence of such lesions is lower than in preterm fetal growth restriction. Screening procedures for fetal growth restriction need to identify small babies and then differentiate between those who are healthy and those who are pathologically small. First- or second-trimester screening strategies provide detection rates for late smallness for gestational age <50% for 10% of false positives. Compared to clinically indicated ultrasonography in the third trimester, universal screening triples the detection rate of late smallness for gestational age. As opposed to early third-trimester ultrasound, scanning late in pregnancy (around 37 weeks) increases the detection rate for birthweight <3rd centile. Contrary to early fetal growth restriction, umbilical artery Doppler velocimetry alone does not provide good differentiation between late smallness for gestational age and fetal growth restriction. A combination of biometric parameters (with severe smallness usually defined as estimated fetal weight or abdominal circumference <3rd centile) with Doppler criteria of placental insufficiency (either in the maternal [uterine Doppler] or fetal [cerebroplacental ratio] compartments) offers a classification tool that correlates with the risk for adverse perinatal outcome. There is no evidence that induction of late fetal growth restriction at term improves perinatal outcomes nor is it a cost-effective strategy, and it may increase neonatal admission when performed <38 weeks.
经共识，晚期胎儿生长受限是指在 >32 周时诊断出的情况。这种情况与围产期缺氧事件和神经发育不良的风险增加轻度相关。从组织学上看，它的特征是存在胎盘血管病变（尤其是梗死），尽管这种病变的发生率低于早产胎儿生长受限。胎儿生长受限的筛查程序需要识别出较小的婴儿，然后区分健康婴儿和病理性较小的婴儿。第一或第二孕期筛查策略对孕龄小于 10%的小于胎龄儿的晚期检出率<50%。与第三孕期临床指征的超声检查相比，普遍筛查将晚期小于胎龄儿的检出率提高了三倍。与早期第三孕期超声检查不同，妊娠晚期（约 37 周）扫描可提高出生体重<第 3 百分位数的检出率。与早期胎儿生长受限相反，单独使用脐动脉多普勒血流速度并不能很好地区分晚期小于胎龄儿和胎儿生长受限。将生物测量参数（严重小于胎龄通常定义为估计胎儿体重或腹围<第 3 百分位数）与胎盘功能不全的多普勒标准（母体[子宫动脉多普勒]或胎儿[脑胎盘比]）相结合，提供了一种与不良围产结局风险相关的分类工具。没有证据表明足月诱导晚期胎儿生长受限可以改善围产结局，也不是一种具有成本效益的策略，而且在<38 周时进行可能会增加新生儿入院率。
