A New Marker as Perinatal Predictor: Notch Index of Uterine Artery Doppler Velocimetry

Park, Yong Won; Cho, Jae Sung; Kim, Tae Yoon; Choi, Hyung Min; Kim, Jae Wook

Abstract

Uterine Artery Doppler velocimetry is widely applied to predict pregnancy outcomes.Recent studies of uterine artery early diastolic notch demonstrate that it is good marker forfetal well-being. The early diastolic notch represents the reflected wave of uteroplacentalcirculation. The degree of back flow is reflected by the depth of the notch. The authorspropose a new Doppler parameter, notch index(early diastolic velocity/maximum diastolicvelocity) which is a better indicator of adverse perinatal outcomes than the isolated findingof an early diastolic notch. Its ability to predict adverse perinatal outcomes was evaluatedin 121 pregnant women beyond the 28th weeks of gestation showing early diastolic notch.The incidence of adverse perinatal outcome(five minute Apgar score<7, cesarean sectiondue to fetal distress, admission to neonatal intensive care unit, or perinatal death) was 100% when the notch index was below 0.7. When the notch index range was 0.7~0.8, 0.8~0.9and greater than 0.9, the incidence of adverse perinatal outcome was 72.4%, 46.6%, and 25%, respectively. This study suggests that notch index could be used as new a marker topredict adverse perinatal outcome.