At what age do you think a dog should be fixed?

This is an interesting topic for me.

I personally believe that a dog can be neutered or spayed as early as 8 weeks with no ill affects. In fact, I think pups actually heal faster and that the surgery is less traumatic at a younger age, and this certainly makes any possibility of the dog reproducing go to zero.

There are vets who won’t do these surgeries until the animal is 4-6 months, vets vary a bit, but to me, getting the animal fixed by 6 months, before they are old enough to reproduce or develop a lot of bad habits, seems important.

But, I’ve seen a few people saying they think they should wait until the dog is “fully mature” to get it fixed. Meaning, wait till the dog is 1.5-2 years of age. Their reason being – well, I’m not really sure what their reason is as the only thing I see happening by waiting is reproducing or the opportunity to develop behavioral problems associated with intact dogs.

So I’m curious what people believe and WHY they believe it. For example, is it something you read? Where? What are the supporting factors? Is it something a vet told you? Did the vet have supporting literature? Or is it just something you heard and … you took someones word for it without asking for or seeing supporting facts?
Puppylove – in my experience, the older the dogs get, the harder the surgery is on them. Puppies heal FAST. It’s the adults, especially the females, that seem to have troubles after surgery. Just my observation.
And I should mention that yes, I think males should be allowed to wait until things drop and any puppies that are so small the surgery would be very risky should wait till they’re a bit bigger. But in general, I don’t see any harm from fixing puppies that are 8 weeks old.
GSD … I am a biologist and I have done my research. Most of what you’re quoting is … nonsense according to the research I’ve done. So … get over yourself. lol!
I’m still waiting for VALID research type links. Anyone can post anything they want on a website. In fact, most website information has very little credibility to me. Now .. link me to a vet journal where the study has been done and peer reviewed … different story.

And … as for behavioral problems. OMG, how many times a day around here do people say “neuter your dog” as the answer for the dog marking inside the house. But some of you don’t see what behavioral problems there could be … what about wondering? What about dominace/aggression? What about types of cancer that are more common in intact dogs?