When a female is not spayed she will go Intl heat every few months and bleed so you will have to put a diaper on her. You will also have to be careful when walking her that she doesn't attract the attention of male dogs. Before my pup was spayed a French bulldog followed her on one of our walks and I had to return him to his home. He tried to mate her (which was hilarious but might not have been if he had been, say, a Rottweiler) and before that I hadn't realized she was in heat. Its not a fun time