Aside from the obvious reasons, do you know what you are doing as far as breeding? Not trying to offend, I just don't know your background? Do you have decades of experience and have successfully bred gsd's for the betterment of the breed and have you had them in dog sport, titled... I mean I'm just not sure if this would be your first time or if you are a long standing hobby breeder or what? Like I said, I don't know your background BUT if this would be your first time, I would stay away from it and leave it to the professionals, plus your dog is older, these are her golden years. Just love her and leave her be as far as the breeding.