Just thought I'd add that I got a job when I was 5 months pregnant - they knew full well that I was UTD and they were more than happy to hire me. I finished up with them 1 week before DS was born, and I didn't get maternity leave of course. It suited their needs and it suited mine too.
Don't assume that no-one will want to hire you when you are pregnant, you should still try. You might be surprised.

Oh, and a SAHM is a great job too - tougher than your DP thinks! One day without you around, and he'll change his mind, i'm sure.