EP16.04: The value of uterine artery Doppler at 18–24 weeks' gestation in predicting adverse pregnancy outcomes among pregnant women with chronic hypertension

Abstract

To evaluate the value of uterine artery Doppler in predicting adverse pregnancy outcomes among women with chronic hypertension in a tertiary hospital. This is a retrospective diagnostic validity study evaluating the value of uterine artery (UA) Doppler at 18-24 weeks age of gestation in predicting adverse pregnancy outcomes among women with Chronic Hypertension (CH) in a tertiary hospital from January 1, 2012 to December 31, 2013, who delivered 24 weeks or more. CH was defined as persistent BP greater than 140/90 mmHg diagnosed before pregnancy or before 20 gestation. Abnormal UA Doppler was described as the presence of an elevated uterine artery resistance index or the presence of a diastolic notch or both. Patients diagnosed with fetal congenital anomaly, other medical problems and higher order gestation were excluded. Fifty-five % CH women had an abnormal UA Doppler and 45%of them had normal results. Among the CH patients with abnormal UA Doppler, the most common adverse pregnancy outcomes were superimposed pre-eclampsia (SPE) (57%), preterm delivery (43%), and IUGR (27%). The findings of abnormal UA Doppler has a high sensitivity of 92.6% and specificity of 63.3% for the development of SPE, with a PPV of 57% and a high negative predictive value of 94%. The positive likelihood ratio (LR) of CH women with abnormal UA Doppler to develop SPE is 2.5 higher compared to those with normal UA Doppler. Abnormal UA Doppler has a sensitivity of 38.1% and a specificity of 83.3% to have babies that are SGA with a positive LR of 2.29, PPV of 72.7% and negative predictive value of 53.6%. Abnormal UA Doppler has a low sensitivity of 5% and but a high specificity of 100% for stillbirth with a PPV 100% and negative predictive value of 46%. UA Doppler study between 18-24 weeks gestation among CH women could be a good predictor and screening tool to asses high risk women to develop adverse pregnancy outcomes especially superimposed pre-eclampsia.