C-section??
This question gets asked here a lot, look back and you'll find lots of answers.
My two cents is that my stomach and my vagina are not connected, so I don't see how one would have any bearing on the other. That being said, I had a c-section with my first baby pre wls, and a vaginal birth with my second, post op. So, I guess I really break that mold. I'd say if anything you're less likely to need a c-section because obesity is one of the risk factors that causes people to need them more often.
My 2 pre wls babies and 1st post WLS baby were all vaginal deliveries! This one may be c-section, but it has to do with my baby being breech and not wanting to turn, not that I am a RNY patient. I really want to know why these people that say that actually say that! Like Paula said, 2 completely different parts of the body! I was considered "High Risk" by my OB due to RNY, but then they took me off the high risk clinic just to be put back on due to meds I have to take for a neurological disorder. So you don't even have to be high risk throughout your pregnancy if they see you are doing well.