Reply #20: I always spayed/neutered any dog I've owned...

[Technowitch]

...because I did not want to be responsible for adding to the unwanted pet population. I never saw it as 'making my dog suffer', but preventing the suffering of a potential litter of puppies for whom a home can't be found.

Leash, back yard -- it doesn't matter. Dogs can and do get loose. And not everybody is as responsible as you are.

Or, to put it another way, how'd you like to get a phone call someday from a neighbor, "Your dog got my grand champion poodle pregnant! I expect you to deal with the litter AND I'm gonna sue you for damages..."

Just sayin'. Also, as others have commented, male dogs do seem more tractable w/out those bits.