it can vary, for instance where i had my VBAC, it was 6 hours to get from 3 cm to 10 cm
however, i would be inclined to ask that you are treated as an individual and if your labour is normal, and you and baby are tolerating labour well, then the time limits are lifted, and you are not given a section, just beacsue it is policy and a certain amount of time has elapsed
your best chance of a succesful VBAC is spontaneous labour, mobility, no epidural and lots of support during the birth IMO and IME
In my hospital it was a 1hr time limit on the 2nd stage (pushing). I just made it. The midwife was getting worried that she'd need to call in doctor and they would wisk me off to the ot for cs (that's what dh told me later. At the time I was just vaguely aware of the time.
There was a time limit for the first stage also, but as it happenned I turned up 10cm dilated anyway so that wasn't an issue. (We reached hospital so late by mistake and I would not recommend that you leave it so late as it could be dangerous.)
I had a doula which I would highly recommend. It made everything so much less stressful.
I was in labour for 12 hours with DD - VBAC; they said that after an hour with the pushing they would take some decision. However, it was longer than that. Also, it didn't mean a c-section, I had some ventouse in the end. And then he would have tried forceps he said if the ventouse didn't work. So, the c section was the very last resort. But as I have said on here before, I had a very lucky time with fantastic support for my VBAC at Homerton in London.
I agree a doula would be useful, particularly if you have less sympthetic hosptial staff.
no, both stages can have a limit.. it is labour itself, the contractions that can put pressure on the scar, but as i posted lower down, if you and baby are tolerating labour well, there is no reason for time limits to be adhered too simply because it is policy.