I'm always hesitant to order/buy these thypes of bras as I am normally a 38DDD-40DD.  Usually if the boobs are contained then the area around the ribs is too large to do any good, or if I can get it tight enough to fit around me, then the girls aren't contained.  I ordered the XL and not only does it offer support (albeit little) but it fit boobs and ribs!  I know it will be of great use when my milk finally comes in and I will probably orber a size smaller for when the baby is out of the belly!