Parry Samuel, Sciscione Anthony, Haas David M, Grobman William A, Iams Jay D, Mercer Brian M, Silver Robert M, Simhan Hyagriv N, Wapner Ronald J, Wing Deborah A, Elovitz Michal A, Schubert Frank P, Peaceman Alan, Esplin M Sean, Caritis Steve, Nageotte Michael P, Carper Benjamin A, Saade George R, Reddy Uma M, Parker Corette B
Departments of Obstetrics and Gynecology at the University of Pennsylvania School of Medicine, Philadelphia, PA.
Christiana Care Health System, Newark, DE.
Am J Obstet Gynecol. 2017 Nov;217(5):594.e1-594.e10. doi: 10.1016/j.ajog.2017.06.013. Epub 2017 Jul 13.
Trophoblastic invasion of the uterine spiral arteries substantially increases compliance to accommodate increased blood flow to the placenta. Failure of this process impedes uterine artery blood flow, and this may be detected by uterine artery Doppler flow studies. However, the clinical utility of uterine artery Doppler flow studies in the prediction of adverse pregnancy outcomes in a general population remains largely unknown.
We sought to determine the utility of early second-trimester uterine artery Doppler studies as a predictor of small-for-gestational-age neonates.
Nulliparous women with a viable singleton pregnancy were recruited during their first trimester into an observational prospective cohort study at 8 institutions across the United States. Participants were seen at 3 study visits during pregnancy and again at delivery. Three indices of uterine artery Doppler flow (resistance index, pulsatility index, and diastolic notching) were measured in the right and left uterine arteries between 16 weeks 0 days' and 22 weeks 6 days' gestation. Test characteristics for varying thresholds in the prediction of small for gestational age (defined as birthweight <5th percentile for gestational age [Alexander growth curve]) were evaluated.
Uterine artery Doppler indices, birthweight, and gestational age at birth were available for 8024 women. Birthweight <5th percentile for gestational age occurred in 358 (4.5%) births. Typical thresholds for the uterine artery Doppler indices were all associated with birthweight <5th percentile for gestational age (P < .0001 for each), but the positive predictive values for these cutoffs were all <15% and areas under receiver operating characteristic curves ranged from 0.50-0.60. Across the continuous scales for these measures, the areas under receiver operating characteristic curves ranged from 0.56-0.62. Incorporating maternal age, early pregnancy body mass index, race/ethnicity, smoking status prior to pregnancy, chronic hypertension, and pregestational diabetes in the prediction model resulted in only modest improvements in the areas under receiver operating characteristic curves ranging from 0.63-0.66.
In this large prospective cohort, early second-trimester uterine artery Doppler studies were not a clinically useful test for predicting small-for-gestational-age babies.
滋养细胞对子宫螺旋动脉的浸润显著增加血管顺应性，以适应胎盘血流量的增加。该过程失败会阻碍子宫动脉血流，这可通过子宫动脉多普勒血流研究检测出来。然而，子宫动脉多普勒血流研究在一般人群中预测不良妊娠结局的临床效用仍 largely 未知。
我们试图确定孕中期早期子宫动脉多普勒研究作为小于胎龄儿预测指标的效用。
在美国 8 家机构，将孕早期有存活单胎妊娠的未产妇纳入一项观察性前瞻性队列研究。参与者在孕期接受 3 次研究访视，并在分娩时再次访视。在妊娠 16 周 0 天至 22 周 6 天之间测量左右子宫动脉的三个子宫动脉多普勒血流指标（阻力指数、搏动指数和舒张期切迹）。评估了预测小于胎龄（定义为出生体重低于胎龄第 5 百分位数[亚历山大生长曲线]）时不同阈值的检验特征。
8024 名女性的子宫动脉多普勒指标、出生体重和出生时的孕周数据可用。358 例（4.5%）出生儿的出生体重低于胎龄第 5 百分位数。子宫动脉多普勒指标的典型阈值均与出生体重低于胎龄第 5 百分位数相关（每项 P <.0001），但这些临界值的阳性预测值均<15%，受试者操作特征曲线下面积范围为 0.50 - 0.60。在这些测量的连续量表中，受试者操作特征曲线下面积范围为 0.56 - 0.62。在预测模型中纳入母亲年龄、孕早期体重指数、种族/族裔、妊娠前吸烟状况、慢性高血压和孕前糖尿病，仅使受试者操作特征曲线下面积有适度改善，范围为 0.63 - 0.66。
在这个大型前瞻性队列中，孕中期早期子宫动脉多普勒研究并非预测小于胎龄儿的临床有用检测方法。
