Ok, so now I'm a little freaked out.
I don't prewash my fabrics, ever. Never had a problem. I've also always used poly batting, because, well, cotton batting is just too damn expensive. BUT, I bought some last year when it was on sale at 50% (still cost 12 bucks a meter, after the discount!) and have been saving it for a special quilt. I was going to use poly batting for my baby quilt that I just finished, but when I went downstairs to get it, I couldn't find any, I guess I used it all up, so I took out the cotton batting.
OMG, what a dream to work with!!! I spray basted, no pins or anything, and it all stayed super nice, no puckers, super smooth, no wrinkles in the back... WOW!!!
However, now I'm faced with the washing problem. I wouldn't prewash my batting, but now that it's in the quilt, I'm not sure I'm supposed to put it in the dryer? I did FMQ meandering quilting on it, relatively close loops, so I don't think it would bunch up or fall apart or anything in the wash, but I'm not sure if I'm supposed to dry in flat or in the dryer. I love the look of the fabric that shrinks in the dryer, which is one of the reasons I don't pre-wash, and it's always looked great with poly-batting once it's out of the dryer. One of the ladies at work today was telling my mother to never put cotton batting in the dryer because it will come apart and bunch up and pucker and look awful after. I know she quilts by hand, and her quilting is not very close together, so maybe that's why she was saying that? I dunno, I'm too scared to wash my quilt now, lol!
P.S. it's a baby quilt for my son, so it's GOING to get dirty and need washing pretty often...