Doppler Ultrasound for Fetal Assessment in High Risk Pregnancies

Abstract

Background When it comes to the provision of antenatal care or research, pregnant women tend to be divided into low- and high-risk populations; however, the boundaries between the groups are often blurred. For most researchers, ‘high-risk status’ includes maternal conditions associated with increased perinatal mortality and morbidity such as diabetes, hypertensive disorders (chronic hypertension and pre-eclampsia) and cardiac disorders. The waveform analysis of the feto- maternal circulation by Doppler ultrasound has become a quick and a simple way for the assessment of fetal well-being in high-risk pregnancies. It helps identify fetuses at risk of hypoxia and acidaemia, when the results are applied clinically; they contribute to reduced perinatal mortality rates. Objectives The main objective of this study is to evaluate Doppler flow indices as an index for assessing fetal wellbeing in high-risk pregnancies. Methods A total of 40 pregnant women with singleton pregnancies at a gestational age ≥3234 weeks were included in this study, 30 of them had a high risk factor were selected as 10 preeclampsia patient, 10 gestational diabetes patient, 10 cardiac patient, the remaining 10 women had no obstetric disorder or any risk factor were selected as control. All pregnant women underwent uniform antenatal assessment protocol that includes an Ultrasound examination and Doppler evaluation of fetoplacental circulation: umbilical artery (UA), middle cerebral artery (MCA) and ductus venosus (DV) Doppler ultrasound studies. Results Our findings showed no statistically significant difference in the Doppler indices between gestational diabetes group and control group. There was only a considerable change in DV Doppler waveform in this study that is also insignificant. At preeclampsia group, it was found that there was statistically significant difference regarding UA RI, MCA RI, and MCA RI/UA RI ratio compared to control group. In the cardiac group, fetal Doppler indices were comparable to those of the control group. Conclusion The result of the present study suggest that Doppler indices in the third trimester may be useful markers of fetal well-being in high risk pregnancy. Hypertensive disorders with pregnancy can be considered the most important indication for third trimester Doppler examination. Two-vessel examination in these cases seems a good practice.