We too are hoping to start a family soon. We are starting the adoption process soon and have always planned on her staying home once we started our family.
I was a stay at home fiancee for about a year.

Talk about hard to talk about in public!

But I'd been forced to quit my job by a bullying boss, then just couldn't find anything else, and finally we gave up and I stopped trying to find work, and focused on planning our wedding. (again, talk about hard to mention in public!)
Then I got pregnant and was too exhausted to think about working, and it just went on. We plan on homeschooling, and so it just doesn't make sense for me to find a paying job, even though he's getting older now.
Anyway, even at home *parents* sometimes have a hard time explaining to people "what" they do...if anything it will give you guys some time to get your "stories" straight (even now my husband will STILL use the word "just" before "stays at home with our son", and that is absolutely maddening, even though I know he doesn't feel that it's "just" anything, LOL).

It will get your walls of "I don't care what others think" up.
AND taking time now, before you even start the adoption process, will give you guys time to get used to the finances of having one person working! And that is a very big luxury that I highly recommend to people thinking of "just" (ha ha ha) staying home.
Good luck with the decision, and with the adoption process!!!