This is the second Medela sleep bra I ordered from Amazon, and boy am I glad I did. The first one I ordered was polyester and kept riding up--I didn't realize it was polyester when I bought it. This one though is cotton and everything I thought the first one was going to be--comfortable, doesn't ride up, and has a nice amount of support for a sleep bra. You want to sleep in cotton, not polyester, so make sure you order the right kind!