This is an interesting topic. Personally I would define a 'normal' birth as one that didn't require intervention. I know many will disagree with me, but I also don't necessarily consider internals to be intervention, or even gas and maybe even pethidine This is because these are options the woman can take that don't necessarily impact negatively on her ability to birth her baby. An epidural is different, it renders her bedridden which does impact on her ability to birth.

In my book, a natural birth is one that involves no intervention and no drugs.

But on a side note I was chatting with a friend the other day who had her bub a few months ago. She was saying, that aside from herself, she only knew one other person who had had an unassisted birth. I found that staggering. But then when I started to think about it, I can actually say that she and the person she was referring to are the only people I know (IRL) that have had an unassisted birth (among our peers, not necessarily parents generation). So out of about 20 (30 tops) that 2 women. Now that is scary!