Role of Ultrasonography and Color Doppler in the Assessment of High-Risk Pregnancies and Their Accuracy in Predicting Fetal Outcome.

Introduction Various methods are employed to evaluate the well-being of the fetus in high-risk pregnancies which consists of a biophysical profile (BPP), a non-stress test (NST), and daily fetal movements. Detection of aberrant blood flow in fetoplacental beds has been revolutionized by recent developments in ultrasound technology, such as color Doppler flow velocimetry. The cornerstone of maternal and fetal care is lowering maternal and perinatal mortality and morbidity is antepartum fetal surveillance. Doppler ultrasound is a non-invasive way of obtaining a qualitative and quantitative evaluation of maternal and fetal circulation and is utilized to investigate complications like fetal growth restriction (FGR) and fetal distress. Thus, it is useful in making distinctions between fetuses that are truly growth restricted and small for gestational age and healthy fetuses. The aim of the current study was to determine the role of Doppler indices in high-risk pregnancies and their accuracy in predicting fetal outcomes. Material and methods This prospective cohort study included 90 high-risk pregnancies in the III trimester (after 28 weeks of gestation) on whom ultrasonography and Doppler were performed. Ultrasonography was performed using PHILIPS EPIQ 5, a curvilinear probe of frequency 2-5MHz. Gestational age was determined with a biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femoral length (FL). Placental grading and position were noted. Estimated fetal weight and the amniotic fluid index were calculated. BPP scoring was done. Doppler study was conducted and the findings of Doppler indices that is pulsatility index (PI) and resistive index (RI) of the middle cerebral artery (MCA), umbilical artery (UA), and uterine artery (UTA), and cerebroplacental (CP) ratio in these high-risk pregnancies were documented and compared with standard. The flow patterns in MCA, UA, and UTA were also assessed. These findings were correlated with fetal outcomes.  Results Among 90 cases, the common high-risk factor in pregnancy was preeclampsia without severe features (30%). Growth lag was present in 43 (47.8%) participants. Among the study population, HC/AC ratio was increased in 19 (21.1%) participants which indicates asymmetrical intrauterine growth restriction. Adverse fetal outcomes were seen in 59 (65.6%) of the subjects. CP ratio and UA PI had better sensitivity (83.05% and 79.66%, respectively) and positive predictive value (PPV) (87.50% and 90.38%, respectively) in identifying the adverse fetal outcomes. Diagnostic accuracy of CP ratio and UA PI (Accuracy=81.11%) was highest in predicting adverse outcomes than all the other parameters. Conclusion CP ratio and UA PI had better sensitivity, PPV, and diagnostic accuracy in identifying adverse fetal outcomes than other parameters. The study's findings support that the use of color Doppler imaging in high-risk pregnancies will help in the early identification of adverse fetal outcomes and aid in early intervention. This study is non-invasive, simple, safe, and reproducible. This study can also be performed bedside in high risk and unstable patients. This study is required to accurately assess fetal well-being in all high-risk pregnancies in order to improve fetal outcomes and to incorporate this procedure as a part of the protocol for the assessment of fetal well-being in these patients.