I'm not sure I agree with the "throw money at the problem" (to use a phrase from La Thatch), well, not entirely, anyway.
Yes, I might do that in the short run but...
I'm an old "Penelope Leach"-style parent, and one of the great things I read in one of her parenting books was her somewhat dry overview of gender, labour and parenting. She observed that supposed equality between the sexes often goes out of the window when the children arrive. That is experienced as a shock, partly because the fact that men (usually) do very little of the home work is disguised pre-children by the fact that a lot of household tasks are contracted out.
Now, you are pre-children, and you already know your dh is doing less. Yes you can contract out a lot of those tasks, now, and after your child arrives. But here's the thing, Penelope was pointing out that tasks expaaaand after the baby arrives, in ways that you can't, completely, contract out.
That suggests that, while you might well throw some money at it now, this problem isn't going to go away (you've already guessed it won't) and it really would be good to have a (very, very firm) discussion of it now. Ideally, before maternity leave, which can set patterns of you taking huge amounts of responsibility as "your" job set in stone.
I think telling him, and making it clear with action, how seriously you take it is the way to go.
And it can work. One of friend's dhs was like this, and he shaped up after some firm talk. Though that was post-baby. And she did, actually, kick him out (for three days) once. though hopefully it won't come to that.
And good luck with the pregnancy!