A couple of months ago I caught my dogs mating...my female isn't spade but my male is neutered. Well, my female is pregnant, at least she's showing all the signs...belly hanging low, nipples are swollen and filled with milk...Can she be?? She hasn't been around any other male dogs. I thought maybe this was a "ghost" pregnancy but now I'm not so sure! So is neutering 100% effective? I know its not 100% for humans, but dogs get them snipped off so I thought it would be impossible! HELP!!