MammyShirl
Active Birth classes are actively encouraged and promoted where I live, and I did a six week course with a qualified yoga teacher and ex midwife. I cannot endorse them enough. The classes covered labour and birth in lots of detail, yoga for pregnancy and preparation for birth, and options for active birth positions. We practiced the positions in the classes, and at the final session, with our birth partner....quite a strange experience when you're not actually in labour, but retrospectively, it was definitely helpful!
My birth was relatively 'easy' and I put that down to the yoga and active birth classes, plus keeping as active as possible throughout pregnancy. I sat on a chair the 'wrong' way round, for early labour, did lots of hip swaying early on too, tried all fours (didn't like it), and eventually found that being at about a 45 degree angle worked! Unfortunately for dh, this meant that I leant against his chest standing up for the last two hours of my labour - he had to have a pillow eventually as my head was bruising his chest (ha!). (Had the option to lean against the wall, but felt that dh should share the experience!!)
I did feel tired towards the very end, and wanted to sit down (not an option by then!). My labour was quite short too, (about 5 hours in total), so keeping as active and fit as poss in the run up to the birth is v. important. In terms of your birth plan, I know they are encouraged by all the books and the midwives, but in my experience, (and almost everyone I know!), they tend to go out of the window anyway, just because things happen and you have to go with them. Mine didn't even come out of my bag, although, admittedly, dh was well briefed, and my labour was not complicated. The important thing is knowing your options and understanding what can happen so that you feel in control if interventions become necessary. (Also learnt this on the course!)
The best thing about having an active birth is feeling in control. I understood everything, and once I got into the second stage, I got my 'business' head on, and I felt totally on top of what I needed to do.
I felt like you too re not being able to imagine the new arrival, and it was a shock (a nice one). My top tip would be to read about parenting as well as about birth - I didn't, and I paid for it!!!!!
Finally, if it helps, dh and I were talking about having the next one days after the first one had arrived.....
HTH