Faculty of Health Sciences, Women's Health and Perinatology Research Group, Department of Clinical Medicine, University of Tromsø, Tromsø, Norway.
Ultrasound Obstet Gynecol. 2011 May;37(5):538-42. doi: 10.1002/uog.8907. Epub 2011 Mar 23.
To describe a new method for measuring uterine vascular resistance (R(uta) ), establish longitudinal reference ranges and explore the relationship between uterine artery (UtA) Doppler indices and R(uta) .
This was a longitudinal study of 53 low-risk pregnancies. Doppler ultrasonography was used to measure UtA velocities, and the pulsatility index (PI), resistance index (RI) and systolic/diastolic velocity (S/D) ratio were calculated. R(uta) was calculated as a ratio between maternal mean arterial pressure and UtA time-averaged maximum velocity.
At 22 + 0 to 39 + 6 weeks of gestation, the mean R(uta) decreased from 1628 to 1180 dyne.s/cm(3) (P < 0.0001). UtA velocities increased (P < 0.0001), whereas the PI (0.79-0.56), RI (0.51-0.40) and S/D ratio (2.0-1.7) decreased (P < 0.0001). R(uta) and the UtA Doppler indices were positively associated (P = 0.003-0.001).
We describe a non-invasive method for measuring R(uta) and provide reference ranges for serial evaluation of UtA velocities, Doppler indices and R(uta) .
描述一种测量子宫血管阻力（R(uta)）的新方法，建立纵向参考范围，并探讨子宫动脉（UtA）多普勒指数与 R(uta)之间的关系。
这是一项对 53 例低危妊娠的纵向研究。使用多普勒超声测量 UtA 速度，并计算搏动指数（PI）、阻力指数（RI）和收缩期/舒张期速度（S/D）比值。R(uta)计算为母体平均动脉压与 UtA 时间平均最大速度的比值。
在 22+0 至 39+6 周妊娠期间，平均 R(uta)从 1628 下降至 1180 达因·秒/厘米³（P<0.0001）。UtA 速度增加（P<0.0001），而 PI（0.79-0.56）、RI（0.51-0.40）和 S/D 比值（2.0-1.7）下降（P<0.0001）。R(uta)与 UtA 多普勒指数呈正相关（P=0.003-0.001）。
我们描述了一种测量 R(uta)的非侵入性方法，并提供了连续评估 UtA 速度、多普勒指数和 R(uta)的参考范围。
