Not as such, but we lived on one income for 6 months before we started trying, which ended up being 16 months before our viable pregnancy, which ended up being 21 months before I actually stopped work. So we're quite used to living on DH's income only, and it's left us with a fairly good savings base.

Good on you for thinking of this now. I know too many people who get pregnant and THEN worry about how they're going to do it.