An episiotomy is where the doctor makes a small cut 'down there' to help make more room for the baby to come out. He will usually only do it if it looks to him like you are going to tear as a tear is much harder to repair than a neat, clean surgical incision.
I tore with my first daughter and it hasn't healed very well so my doc has told me that this time, I'll definitely need an episiotomy to prevent further tearing along my old scar.
It is a scary thought <I'm trying not to think about it just yet>, but I think they give you a local anasthetic to numb the area first.
Nicole - WA - Mummy to 2 Girls (16yrs & 9mths)