I wouldn't for two reasons.
The first is the aforementioned fact that unless your quilt top and back are very dark all over - the print on the fleece will show through.
More important though is because they are polyester fleece and these are baby quilts. I won't use polyester in baby quilts (actually I won't use polyester at all but that's because I don't like it) because of the burn results. Polyester "melts" and can catch fire much easier than natural fibers.