Color Doppler imaging of the uterine artery in pregnancy: normal ranges of impedance to blood flow, mean velocity and volume of flow

S Bower; S Vyas; S Campbell; K H Nicolaides

doi:10.1046/j.1469-0705.1992.02040261.x

Color Doppler imaging of the uterine artery in pregnancy: normal ranges of impedance to blood flow, mean velocity and volume of flow

Ultrasound Obstet Gynecol. 1992 Jul 1;2(4):261-5. doi: 10.1046/j.1469-0705.1992.02040261.x.

Authors

S Bower¹, S Vyas, S Campbell, K H Nicolaides

Affiliation

¹ Department of Obstetrics and Gynaecology, King's College Hospital, London, UK.

PMID: 12796952
DOI: 10.1046/j.1469-0705.1992.02040261.x

Abstract

In a cross-sectional study of 215 healthy women with singleton pregnancies at 18-42 weeks' gestation, color Doppler imaging was used to identify the main uterine arteries for subsequent pulsed Doppler studies. Flow velocity waveforms were obtained and indices of impedance, mean blood velocity and vessel diameter were measured, and the total volume of blood flow to the uterus was calculated. Impedance to flow decreased, I whereas blood velocity and volume flow increased significantly with gestation. Furthermore, impedance to flow was lower and velocity higher in the placental uterine artery, i.e. closest to the main bulk of the placenta, than in the non-placental artery.