Uterine Artery Doppler of the Gravid Uterus as a Predictor Identifying At-Risk Pregnancies: A Meta-Analysis

摘要

Uterine artery Doppler has been a useful aid in the sonographic evaluation of uteroplacental hemodynamics of the gravid uterus. Pulsatility index, resistive index, and systolic/diastolic ratio can be calculated and interpreted in the evaluation of blood flow. The waveform itself can be evaluated for diastolic notching and used to interpret the qualitative appearance of the blood flow. In addition to the hemodynamic characteristics, practitioners have incorporated maternal serum tests to attempt to isolate at-risk candidates. This article summarizes the effectiveness of each methodology, with a primary focus on an at-risk population, since studies of low-risk populations have not demonstrated significant sensitivity for prediction of complications such as pre-eclampsia, placental abruptia, or fetal demise. During a routine low-risk pregnancy, the uterine arteries undergo a trophoblastic change in which the hemodynamics transition from a high resistive blood flow to a low resistive blood flow (Figure 1). This is to perfuse the uteroplacental system with oxygenated blood to allow for adequate fetal development. Complications of fetal development and well-being can occur when this transition is compromised. There are predisposing health conditions that have been identified with interrupting this hemodynamic transition such as hypertension, diabetes, autoimmune disorders, clotting disorders, and renal disease, as well as maternal factors, such as body mass index (BMI) and ethnicity, that increase chances of pregnancy complications. Uterine artery Doppler has been a useful aid in the sonographic evaluation of uteroplacental hemodynamics of the gravid uterus. Over the years, practitioners have been using it as a predictive tool to analyze or isolate pregnancies that are at-risk for adverse outcomes. Numerous parameters can be calculated in the evaluation of the blood flow; typical quantitative values used include the pulsatility index (PI), resistive index (RI), and systolic/diastolic (S/D) ratio.