What zeo said is the best questions to ask. If it’s only the waist you’re worried about ive found jeans that are 100% or almost 100% cotton will expand a little bit from when you first get them, but given these seem to have a lot of stretch fabric based on the site I’d be worried about stretching too much and causing some kind of distortion or rip. I don’t have a whole lot of experiences with jeans that stretchy though so I could be off base on that