I am a solid 16, 5'6", and ordered the xxl. It fits me perfectly - no stretching and comes down to my ankles. There is a modesty panel behind the buttons, so that if it is a little tight it still shouldn't show gaps, but I suspect a woman with larger than a C cup might find it too tight up top. I gave it 4 stars because there were some strings that I needed to cut, and also because I am concerned that the elastic button holders will break easily.