Friday, January 14, 2011

How to perform lower uterine segment measurement

Here is a description of how one doctor performs a uterine segment measurement.  This information is from Dr. Patrick Rozenberg, the author of the best studies on the subject. He does it via transabdominal ultrasound (the kind that goes over your belly), but my sonographer actually did it via transvaginal ultrasound because she thought she could get better readings that way (and, in fact, a later study suggested that she was correct).

I measured a 4mm when my sonographer did it.  Dr. Rozenberg's 1996 study on this measurement suggested a cut-off of 3.5mm; because I had a higher measurement than this, I felt comfortable going forward with my VBAC attempt.
Here's the link to the description of the 1996 study.

Description of how Dr. Rozenberg performs the measurement:

From: [Dr. Rozenberg]
To: [Me]
Sent: Wednesday, August 1, 2007 12:28:00 PM
Subject: RE how to perform ultrasonographic measurement of the lower uterine segment

Transabdominal examination
Between 36 and 38 weeks
Full bladder (visualization of the whole LUS)
Sagittal sections of the LUS
Measure of the thinnest zone (upper third of the LUS)
Calipers at the interface of the bladder and the amniotic fluid-decidua
LUS in an almost horizontal plane
3 measurements (smallest value chosen)

PR(See attached file: SI.5.3.jpg)


Julie said...

I remember Reading your posts on BC when I was attempting my VBA2C and it was super helpful.

Now I was googling the info for a friend and I was so happy to find your blog.

Thanks for taking the time to gathering all in a very accesible way for anyone to find.

Anonymous said...

Thank you so very much for this! I am researching my own VBAC/HBAC at the moment and your website has been so so helpful they recently published a meta-analysis if anyone is interested here it covers all major studies up to 2014 - so looking at over 2000 women.