Someone on my natural childbirth forum posted this link: http://www.natural-pregnancy-mentor.com/vaginal-exams.html
It goes over what a vaginal exam measures and what it does (and doesn't) tell us about the progress of labor. It also goes over the risks, including rupture of membranes and infection. Okay, okay, tell us something we don't know, right?
Here's the good part: The credit is given to midwife Anne Frye for a method for measuring labor progress externally by comparing the location of the fundus (top of the uterus) at the height of a contraction to the zyphoid process (the cartilage at the tip of the sternum/breastbone):
Your birth attendant can determine how many fingerbreadths of space are between the fundus and xiphoid process at the height of a contraction.
# 5 fb = no dilation
# 4 fb = 2 cm
# 3 fb = 4 cm
# 2 fb = 6 cm
# 1 fb = 8 cm
# 0 fm = complete
To some this does not make sense: that the space between your xiphoid and your fundus shortens - becomes narrower - dilation advances since your baby engages more and more as the contractions push him inside the birth canal. Remember, the upper segment of your uterus thickens as labor advances. Your uterus also rises more as contractions intensify. This is also the reason why this must be done at the height of a contraction. Midwives have reported this to be very accurate...and a bonus no fingers where they do not belong!
At first it didn't make sense to me that the fundus gets closer to the zyphod process. I thought, shouldn't the uterus move down as the baby does? But then I got it: as the uterus thins and opens at the bottom, it thickens at the top--that's physics. This method is actually measuring dilation from the TOP of the uterus instead of the bottom. AMAZING!
If this method really works (and midwives say it does), then it could lead to the end of vaginal exams in labor! No more uncomfortable, intrusive exams that increase the risk of infection, and no more getting into uncomfortable positions to be be "checked," and no more ending up stuck in those positions to push.
I am definitely going to be telling my birth attendant about this whenever I have my next baby!