I just discovered the most COMFORTABLE bra on the planet! It's practically one size fits all (I know that sounds too good to be true, but it's true!) so it's awesome for pregnancy because it grows with your boobs.
It's super comfortable (I hate wearing bras, and I actually sleep in this one), it doesn't show back fat like a lot of bras, and your nipples don't show through (I don't know if this is a problem for other people, but some bras don't have enough padding and you can see through).
It's called the Coobie Bra (and I swear I don't work for them, I'm just in love, lol).
They are currently running a deal for buy two get one free, which is awesome. It comes in lots of pretty colors too.
Here's the website: http://shopcoobie.com/