Christina Hendricks is one of my favourite actresses/people. I identify with her, admire her and I think she has great style and grace. But a 38DDD/E? Definitely not. I've no doubt she has many different bra sizes in her collection as her size fluctuates, but if she has a 38E, she has been conned by an inexperienced and/or ignorant sales assistant into buying a bra that is too small in the cup and too large in the band.
If I were in this dress, with this fit, I would feel so incredibly uncomfortable. Who wants that deep crevasse of cleavage from the girls being so squished? You can even see that the breast tissue is out of the dress under her arms.
It also looks like she has a better fitting bra here, but it's hard to tell. It doesn't look as if she has cleavage up to her chin underneath the dress, so it may be that she is wearing the correct size. I would guess her size to be about a 30J/32HH, but that's just a guess based on our similar ribcage and my bust being a cup size (or two) smaller than hers.
If women around the world think Christina is an E cup, no wonder they can't fathom that they could be one.
JM