I just watched the Docco A breech in the system, and the midwife on there said that around 10% of hospital births are intervention free. The other 90% have some form of intervention, be it drugs or help with the delivery, or induction or whatever.

I consider my VBA2C to be a natural birth although I did have AROM at 10cm cos I asked for it. But 3 days of labour, no drugs, respect for my birth plan and doing it my way is my definition of natural birth