A Prospective Study of Doppler Velocimetry in Pregnancy-induced Hypertension in a Rural Population of a Developing Country

Abstract

Background: Pregnancy-induced hypertension (PIH) remains a great challenge to obstetricians. Doppler velocimetry can detect fetal compromise much before other antepartum tests.

Aim: The aim of this study is to detect the changes of uterine artery, umbilical artery and middle cerebral artery in PIH by Doppler velocimetry.

Subjects and Methods: This prospective study was conducted on hundred subjects with PIH. Doppler studies were carried, and parameters recorded in uterine, umbilical and middle cerebral artery (MCA) were Systolic/Diastolic ratio, Resistance Index, Cerebro Placental Index (CPI). Fetal outcomes were monitored. Statistical analysis was performed using Epi InfoTM software (Version 3.5.1, CDC, Atlanta). Test for significance was done with student’s t-test and Chi-square where applicable. A P- value of<0.05 was considered as significant.

Results: Among the 100 subjects, 76 (76%) of fetuses had abnormal and 24% normal umbilical artery Doppler velocimetry; 62% had abnormal and 38% normal MCA Doppler velocimetry; 64% fetuses had abnormal and 36% normal CPI. In 95% of subjects having abnormal umbilical Doppler studies, caesarean section had to be done for acute fetal distress. Incidence of caesarean section was 61% in abnormal MCA group and 63% in abnormal CPI group. Among 14 patients who had abnormal uterine artery Doppler, four developed pre-eclampsia, 2 IUGR. In patients with notches in uterine artery Doppler, 38% developed pre-eclampsia, 38% had IUGR, 13% babies were still born and 25% of newborns required NICU admission. In umbilical artery Doppler, when S/D ratio was abnormal, 60% developed pre-eclampsia, 40% had IUGR and 40% of newborns had to be admitted in NICU.

Conclusion: Doppler study for fetal surveillance in pregnancy-induced hypertension is a very useful device and abnormal umbilical artery and uterine artery velocimetry seems to have worse pregnancy outcomes in the present study. Notch as a single parameter is the best indicator with highest sensitivity and positive predicative values. However, combination of parameters is the best indicator. 

Keywords: Doppler study, fetomaternal outcome, pregnancy-induced hypertension