The Generation R Study Group, Erasmus MC, University Medical Center Rotterdam, P.O. Box 2040, 3000, CA, Rotterdam, the Netherlands.
Department of Paediatrics, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.
BMC Med. 2020 Apr 7;18(1):63. doi: 10.1186/s12916-020-01540-x.
Preterm birth, small size for gestational age (SGA) and large size for gestational age (LGA) at birth are major risk factors for neonatal and long-term morbidity and mortality. It is unclear which periods of pregnancy are optimal for ultrasound screening to identify fetuses at risk of preterm birth, SGA or LGA at birth. We aimed to examine whether single or combined second and third trimester ultrasound in addition to maternal characteristics at the start of pregnancy are optimal to detect fetuses at risk for preterm birth, SGA and LGA.
In a prospective population-based cohort among 7677 pregnant women, we measured second and third trimester estimated fetal weight (EFW), and uterine artery pulsatility and umbilical artery resistance indices as placenta flow measures. Screen positive was considered as EFW or placenta flow measure < 10th or > 90th percentile. Information about maternal age, body mass index, ethnicity, parity, smoking, fetal sex and birth outcomes was available from questionnaires and medical records. Screening performance was assessed via receiver operating characteristic (ROC) curves and area under the curve (AUC) along with sensitivity at different false-positive rates.
Maternal characteristics only and in combination with second trimester EFW had a moderate performance for screening for each adverse birth outcome. Screening performance improved by adding third trimester EFW to the maternal characteristics (AUCs for preterm birth 0.64 (95%CI 0.61 to 0.67); SGA 0.79 (95%CI 0.78 to 0.81); LGA 0.76 (95%CI 0.75; 0.78)). Adding third trimester placenta measures to this model improved only screening for risk of preterm birth (AUC 0.72 (95%CI 0.66 to 0.77) with sensitivity 37% at specificity 90%) and SGA (AUC 0.83 (95%CI 0.81 to 0.86) with sensitivity 55% at specificity 90%). Combining second and third trimester fetal and placental ultrasound did not lead to a better performance as compared to using only third trimester results.
Combining single third trimester fetal and placental ultrasound results with maternal characteristics has the best screening performance for risks of preterm birth, SGA and LGA. As compared to second trimester screening, third trimester screening may double the detection of fetuses at risk of common adverse birth outcomes.
早产、小于胎龄儿（SGA）和大于胎龄儿（LGA）是新生儿和长期发病率和死亡率的主要危险因素。目前尚不清楚妊娠的哪个时期进行超声筛查最佳，以识别有早产、SGA 或 LGA 风险的胎儿。我们旨在研究单独或联合使用第二和第三孕期超声以及妊娠开始时的母亲特征，是否可以最佳地检测有早产、SGA 和 LGA 风险的胎儿。
在一项针对 7677 名孕妇的前瞻性基于人群的队列研究中，我们测量了第二和第三孕期的估计胎儿体重（EFW）以及子宫动脉搏动和脐动脉阻力指数，作为胎盘血流测量值。将 EFW 或胎盘血流测量值<第 10 个百分位数或>第 90 个百分位数视为阳性筛查。母亲年龄、体重指数、种族、产次、吸烟、胎儿性别和出生结局的信息可从问卷和病历中获得。通过接受者操作特征（ROC）曲线和曲线下面积（AUC）以及不同假阳性率下的灵敏度来评估筛查性能。
仅母亲特征以及与第二孕期 EFW 联合使用，对每种不良出生结局的筛查性能均为中等。将第三孕期 EFW 添加到母亲特征中可改善筛查性能（早产的 AUC 为 0.64（95%CI 0.61 至 0.67）；SGA 的 AUC 为 0.79（95%CI 0.78 至 0.81）；LGA 的 AUC 为 0.76（95%CI 0.75；0.78））。将第三孕期胎盘测量值添加到该模型中，仅改善了早产风险的筛查（AUC 为 0.72（95%CI 0.66 至 0.77），特异性为 90%时的灵敏度为 37%）和 SGA（AUC 为 0.83（95%CI 0.81 至 0.86），特异性为 90%时的灵敏度为 55%）。与仅使用第三孕期结果相比，联合使用第二和第三孕期胎儿和胎盘超声并不能提高性能。
将单独的第三孕期胎儿和胎盘超声结果与母亲特征相结合，对早产、SGA 和 LGA 的风险具有最佳的筛查性能。与第二孕期筛查相比，第三孕期筛查可将风险胎儿的检出率提高一倍，这些胎儿有常见不良出生结局的风险。
