CHRONIC HYPERTENSION IN PREGNANCY - COLOR DOPPLER INVESTIGATION OF UTERINE ARTERIES AS A PREDICTIVE TEST FOR SUPERIMPOSED PREECLAMPSIA AND ADVERSE PERINATAL OUTCOME

To determine if uterine artery Doppler velocimetry is useful in identi fying chronic hypertensive pregnancies at risk for superimposed preecl ampsia and adverse perinatal outcome. Resistance index (RI) was assess ed by color velocimetry at the level of uterine arteries at 23-24 week s of gestation in 42 women with chronic hypertension. The ''lowest'', the ''highest'' and the ''average'' values were compared to select the most predictive index for superimposed preeclampsia. intrauterine gro wth retardation (IUGR), birth weight lower than 2500 g and gestational age at delivery less than 36 weeks. Nine patients developed superimpo sed preeclampsia (21%) and 15 delivered before the 36(th) week of gest ation (36%); 4 babies were IUGR (10%) and in 18 cases birth weights we re below 2500 g (43%). Statistical analysis of Doppler findings showed that abnormal val ues of ''lowest RI'' were significantly correlated with adverse pregnancy outcome. Color Doppler analysis of uterine arte ries is able to Select chronic hypertensive pregnant women at risk of superimposed preeclampsia and poor perinatal outcome.