Normal value of pulsatility index of umbilical artery in second and third trimester of pregnancy.

This cross sectional study was carried out on 60 pregnant Bangladeshi women in the department of Radiology and Imaging, BIRDEM for measurement of Pulsatility Index (PI) of umbilical artery of their fetuses by duplex colour Doppler sonography during 2nd and 3rd trimester of pregnancies. Considering total 2nd and 3rd trimesters the mean PI value of umbilical artery was 1.24 (SD +/- 0.27). While considering the gestational in separate trimesters, study showed that the value of PI in 2nd trimester was 1.33 (SD +/- 0.29) and in 3rd trimester PI was 1.18 (SD +/- 0.25). Paired t test shows there was a highly significant (t = 35.79, df = 59, Level of significance = 0.001) difference between mean values of PI in different gestational ages. It was observed that there was gradual decrease of PI value with increase of gestational age (r = -0.207) but this decrease of PI was not statistically significant (p = 0.113). Regression analysis between dependent PI value and independent gestational age showed linear negative relationship but this was not statistically significant (p = 0.11). This study revealed that the Pulsatility index of umbilical artery was decreased with increase of gestational age from 2nd to 3rd trimester.