I didn't realize this garment does not have a split crotch, so you have to take it down from the top to go to the bathroom.  I got the S/M size and it looks like it would fit but I didn't try it on since I plan to send it back.  I am 5'6, 150 lbs and usually wear a size 8T jeans.  It looks very nice and soft and stretchy but with the bra-like straps over the shoulders it just isn't what I wanted.