I developed them during my second pregnancy. I just had a dull ache in my vagina and it was worse after DTD. I don't think it made them any worse though, it was just that the blood is flowing to the area at the time. The ache got worse towards the end and lasted for a couple of months after having DS2, but they went away of their own accord.
I had a c/s with DS1 so I don't think it is reliant on having an assisted delivery the first time.

Beatrix, I am a little scared now having read your post. lol. Hopefully I will make it through this 3rd pregnancy without requiring surgery. And I hope you fully recover soon. Sore vaginas are no fun... but at least they are the fastest healing part of the body!