How interesting that both of you have emeralds in your engagements rings. I do, too! I cracked the first emerald and it fell out. That was after probably 6 or 8 years. We went back to the same store we bought it at and had it replaced. I've cracked the one that's in there now, but it's still in place so I've left it. I keep saying I'll replace it when it comes out, but its still there so I'm still waiting.
I did lose a small diamond out of a pair of earrings, but that's the only diamond I've lost. It is a good idea ot have your rings checked to make sure the prongs are secure and not bent or damaged.