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Antenatal tests

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Original poster

PI and RI values

1 reply

Smoa9 · 24/12/2020 12:03

Just wondering if anyone knows anything about these values? Sonographer mentioned nothing during the scan. I've looked at the report and the values are showing as off the centile to the right? PI 1.21 and RI 0.66. Vmax -90.4. I'm just concerned these values dont seem normal but she didn't mention anything?

OP posts:
Scirocco · 24/12/2020 20:27

PI and RI, if I remember correctly, refer to characteristics of blood flow (pulsatility and resistance of the blood vessels) - different vessels can be measured, but I'm guessing the measurements here refer to either the umbilical or uterine arteries. These numbers change during the course of pregnancy, as do the reference ranges. Vmax is the maximum velocity of blood flow measured (the negative sign just refers to the direction of blood flow at that measurement in relation to the device taking the measurement).

If you think the values are outside the reference ranges for your stage of pregnancy, you could speak with your midwife or doctor for reassurance.

Sorry if that's not much help.

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