If there's a potential pregnancy involved then you need to make sure that you're all on the same page RIGHT NOW about what might happen in the future. If it is really going to bother you if she has a child by this guy, then you need to say so upfront. You also need to work out what's going to happen if such a scenario plays itself out - assuming that the other man is the father, what will the living arrangements be, how will you fit into this child's life etc?
Anyway, she can't tell you that you have to be ok with her getting pregnant, that's something only you can decide for yourself. Are you ok with her possibly getting pregnant by another man? If you are fine, just make sure you've got a plan in case it does happen, if it doesn't, you're going to have renegotiate boundaries.
As for unprotected sex, if she's not using it, I'd be asking to see some evidence that there's no STDs or anything else. If she's having unprotected sex with you both and there's no testing going on, then it's irresponsible in my book.
Right now, you need to be sure that this situation works FOR YOU as well as for your wife. It seems that you're making sacrifices for her, but that none of your needs have even been addressed. Maybe that's because they're already met, but if they're not, then you need to start communicating that.