Hi! Question for those who have already given birth. How much did your…

Hi! Question for those who have already given birth. How much did your belly shrink immediately after childbirth? I'm thinking about what to wear after that. Should I buy something or is there a chance I can fasten my jeans? My legs and hips fit in... If I do buy something, then I don't know how it will look either, I can't try it on ( Please don't write about dresses and sundresses, I understand them well enough) ???