Comparison of foetomaternal circulation in normal pregnancies and pregnancy induced hypertension using color doppler studies.

ABSTRACT

The aim of present study was to assess fetomaternal blood flows in normal and abnormal pregnancies using color doppler indices. Subjects were divided into two groups as Group A of 25 subjects of normal pregnancy as controls and group B of 25 subjects of pregnancy induced hypertension. All the subjects were lying in the age-group of 25-35 years and having 28 to 34 weeks of gestation; the patients were evaluated by detailed history and were subjected to complete general examination. Blood pressure was taken on two occasions at least 6 hours apart. Systemic examination and obstetrical examination was done in all subjects. All cases were subjected to pathological tests- Haemogram, Test for proteins in urine. Ultrasound assessment of fetal growth was done by measuring BPD (Biparietal diameter), HC (Head circumference), FL (Femur length) and AC (Abdominal circumference). Average gestational age and effective fetal weight was then calculated by ultrasound machine. Color Doppler was used to assess the various doppler indices indices Pulsatility index (PI), Resistive index (RI) and Systolic diastolic ratio (S/D ratio) in bilateral uterine, umbilical and middle cerebral arteries and compared to the standard normograms. Percentage of subjects having abnormal doppler indices were calculated. Assessment of percentage of SGA (small for gestational age) fetuses was done in all the three groups. Decline in mean values of all doppler indices was found with advancing gestational age in normal pregnancy suggesting decreased vascular resistance and increased blood flow in fetomaternal circulation. In pregnancy induced hypertensives, the mean values of doppler indices showed a decline as in normal pregnancy but showed an increase (more than 2 S.D. of the mean) for that gestational age in comparison to the control group suggesting increased impedance to blood flow in uteroplacental and fetomaternal circulation. Umbilical artery doppler indices were found to be the most sensitive indicator of uteroplacental and fetoplacental insufficiency in pregnancy induced hypertensives (P=0.001). Thus we concluded that color doppler can detect changes in fetomaternal circulation which correlate strongly with the fetal growth and therefore associated with pregnancy outcome.