I followed the sizing instructions but it turned out a tad loose. Ordering 38 would have been better. They instruct you to measure above the breasts but maybe that is wider than under, I don't know.
I am still able to wear it, particularly that I want it for use during lounge hours. So that is fine. I went back and ordered a couple more playtex of the same kind and two other with underwire. That is how much I found this bra comfortable. The second time around I ordered 38ddd.