Efficacy of doppler velocimetry of the umbilical artery in the defined high-risk groups to determine the fetal outcome

ABSTRACT

Background: Doppler ultrasound provides a non-invasive method of studying the status of various blood vessels. It provides a spectrum analysis of the velocities of moving red blood cells. Doppler sonography can provide useful information in a variety of gynecological and obstetric conditions. In obstetrics, Doppler velocimetry of the uteroplacental and fetoplacental circulation can be used to further investigate complications of pregnancy such as fetal growth restriction, other forms of fetal distress that result from fetal hypoxemia or asphyxia.Methods: In a prospective observational study, 93 pregnancies fitting in the criteria for high risk were evaluated by doppler velocimetry between 28-40 weeks of gestation. The flow velocity time wave forms were examined and quantitated by use of systolic/diastolic (S/D) ratio, resistance index (RI), pulsatility index (PI) values. The outcome of pregnancy was noted.Results: Fetuses with abnormal velocimetry are at higher risk with regard to birth weight, Apgar score, fetal distress, need of cesarean section, need of NICU admission. The patients with absent end-diastolic flow (AEDF)/reversal of end-diastolic flow (REDF) had poor perinatal outcome. Positive predictive value for small for gestational age (SGA) and fetal distress was 75% and 60% respectively. 23.8% babies needed to be kept in neonatal intensive care unit (NICU).Conclusions: Doppler velocimetry can be useful prenatal test for the patients of hypertensive disorder of pregnancy and IUGR. Abnormal doppler waveform changes indicate adverse perinatal outcome. Appropriate and timely interventions guided by doppler study help to reduce perinatal morbidity and mortality.