If you have the surgery, are you going to "spay" her? Then you won't ever deal with this again in the future. It takes a really great surgeon to remove a slug and leave the female capable of breeding anyway. Just something to discuss with your vet.
Wel, I hope it doesn't come to that, and then next spring, feed a little less for the early spring, to discourage egg laying, and give calcium supplements in case she does.
Not to make you paranoid, but keep a close eye on her, especially her tail. My girl threw a blood clot during or after her surgery that lodged in her tail and required it to be amputated the next day.