Does anyone know how the H&M nursing tanks run as far as size? Big, small, normal? Are they cut like a maternity tank (more room in the belly) or like a non-maternity tank?

I'm usually a M/L in tops and a DD, but I like my tanks to be snug (and almost always wear something over them).
For reference, I bought a couple of the Old Navy tanks in a large and they were bigger than I like.