Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
J Matern Fetal Neonatal Med. 2021 Jun;34(11):1768-1773. doi: 10.1080/14767058.2019.1648420. Epub 2019 Aug 1.
We evaluated the ability of third trimester ultrasound to diagnose fetal growth disorders among obese women.
This is a retrospective cohort study of obese nulliparous women who delivered term singleton neonates who had an ultrasound within 5 weeks of delivery. We characterized the sensitivity, specificity, positive predictive value and negative predictive value of ultrasound to detect large-for-gestational age (LGA) and small-for-gestational age (SGA) infants. Antenatally, LGA and SGA were defined as an ultrasound estimated fetal weight >90% or <10% based on the Hadlock formula. Postnatally, LGA or SGA designation was based on gestational age-based birthweight percentiles. Test characteristics were analyzed for the total cohort and by class of obesity (class II, body mass index [BMI] = 35.0-39.9 kg/m versus class III, BMI ≥ 40 kg/m). We compared the area under the curve for receiver-operating characteristic (ROC) curves for different classes of obesity.
Of 690 women, 13 (1.9%) screened positive for SGA and 19 (2.8%) delivered an SGA neonate. In contrast, 158 (22.9%) screened positive for LGA and 97 (14.1%) delivered an LGA neonate. The sensitivity of ultrasound for SGA was 26.3% and the specificity was 98.8%. The sensitivity for LGA was 75.3% and the specificity was 85.7%. The ROC curves did not differ significantly for different classes of obesity ( = .69 for SGA, = .75 for LGA).
Ultrasound in obese women who delivered term pregnancies has a high specificity but poor sensitivity for SGA and a low positive predictive value for LGA.
评估孕晚期超声在诊断肥胖孕妇胎儿生长障碍中的能力。
这是一项回顾性队列研究，纳入了足月分娩的单胎肥胖初产妇，这些产妇在分娩后 5 周内进行了超声检查。我们描述了超声检测巨大儿（LGA）和小于胎龄儿（SGA）的灵敏度、特异度、阳性预测值和阴性预测值。产前，LGA 和 SGA 是指根据 Hadlock 公式，超声估计胎儿体重＞90%或＜10%；产后，LGA 或 SGA 的定义是基于基于胎龄的出生体重百分位数。我们分析了总队列和肥胖程度（Ⅱ类，BMI=35.0-39.9kg/m2 与Ⅲ类，BMI≥40kg/m2）的受试者工作特征（ROC）曲线下面积。
在 690 名妇女中，13 名（1.9%）筛查为 SGA，19 名（2.8%）分娩出 SGA 新生儿。相比之下，158 名（22.9%）筛查为 LGA，97 名（14.1%）分娩出 LGA 新生儿。超声检测 SGA 的灵敏度为 26.3%，特异度为 98.8%。LGA 的灵敏度为 75.3%，特异度为 85.7%。ROC 曲线在不同肥胖程度之间没有显著差异（SGA：=0.69，LGA：=0.75）。
在分娩足月妊娠的肥胖妇女中，超声检查对 SGA 具有较高的特异性和较差的灵敏度，对 LGA 的阳性预测值较低。
