That's a good question, really. My answer is just an opinion, but doctors are generally trained in the pathology of labor and birth and look at it from that perspective: looking for a diagnosis of what could be "wrong." Their tools for diagnosis are pretty much limited to ultrasounds, especially for things like a baby's size, so they place a lot of faith in them. Now, for midwives, I would say the average midwife in the US would
not be placing as much emphasis or trust in an ultrasound because of the very opposite reasons. However, since midwives are the standard practitioner for births in the UK, I think they're more medical-minded and favorable toward interventions from the get-go (the term "medwives" comes to mind).
Do you have a doula? If you don't, and you feel like you might have differing opinions from your care providers in the near future, a doula might be a really good idea for you. She could be a pillar of support as well as kind of run interference for you. And when you're in the throes of labor and feeling a little more desperate, she could be there to remind you that your body was made for it and what your wishes are, so you're less likely to give into outside pressures for things you don't want.
http://www.doula.org.uk/ is the best way to find a doula. If you have limited funds, you can usually find a student doula or one who is still doing her certification to work for a reduced fee or even for free (this is what I had to do). You could also see if your doula could come to appointments with you to provide extra support. One of the things I dreaded was monitoring appointments because that's when they always decided to lay it on thick with the scare tactics.
