We see the message everywhere.. bumper stickers, websites, t-shirts. "Spay & Neuter" your pets. I myself am an avid believer in less regulation, laws, etc., especially pertaining to pet ownership. I believe that good people do the right thing, and people without that sense will continue to potentially do wrong by their pets or others regardless of legislation. In most states, it is commonly illegal to have an unaltered male unless you can prove you are showing or breeding him. Naturally, if you are breeding him, he needs to remain intact. The rescue community can look down upon breeders, but on the whole the truth is that they look down on irresponsible ones. Breeders who do not breed to demand, but breed and breed, without homes in mind, and in extreme cases, may think to discard their bitches once their puppy producing abilities are over. I don't like those people.
From what I have gathered, we tend to find more resistance from male humans regarding altering their male dogs. They personalize it, in a "I don't want anyone doing that to me!" kind of way. I think on the whole, many owners would be good about not letting their unaltered male wander the streets. The reality is, is that an intact male can sniff out a bitch in heat, and may do everything in his power to find a way to escape and rendezvous with the little lady. So before your male is altered, be sure you are absolutely confident that your little man has no such way of escaping what you thought was the impenetrable fortress of your back fence.
Regarding your female, veterinary statistics show that unaltered females have a considerably increased risk of mammary cancer and other conditions such as pyometra if they remain unspayed before their first heat. Statistics show it is not something an owner should put off.
The large question becomes, how young can I get this surgery in my male or female? The reality is, is that technically no age is too young. I have been told this by many veterinarians. Why we do it at 6 months, is because by 6 months your dog's baby teeth should have all given way to the adult ones. If they have not, you can pay for 1 anesthetic procedure to address spay/neuter as well as getting any remaining baby teeth extracted. We do not want to wait for those teeth to fall out if they are not gone by 6 months, as it can lead to some dental problems in the future.
In summary, while I feel there are many medical reasons to address getting your girl spayed, we all understand laziness with both sexes can yield unwanted results. If you are not a responsible breeder, don't breed. I grew up in a small town, where people left their animals unaltered and thought nothing of just giving unwanted puppies to the local mall, should they materialize. I met a man the other day, whose puppy was given to him by an owner who really thought her bitch had no access to males. She, was wrong. Nature is nature, and if you are not careful, your animal doesn't need to be a stray to find a way to procreate!
Spay and neuter. And if you cannot get your puppy from a responsible breeder, save a rescue dog! Or.. just save a rescue dog:)