So long as the fence is intact, highly unlikely. However, estrus cycles (heat) in bitches (female dogs) can trigger very persistent behavior in males, and they may find a way to break in by digging under the fence, or pressing the muzzles into the mesh or boards hard enough to loosen them (I've seen several male dogs with noses bloodied from such attempts, and even thick-gauge mesh broken through). Bitches themselves also tend to be 'needy' of attention during their cycles, and if they are not attended to, they may try to break out of their containment themselves when in heat.
Most dogs can jump a standard chain link fence.
NO
If the female is trying to get pregnant with a male dog then it will go on the males back but if the female dog is going on the males back while pregnant then it may means that they wanted to have another baby.
By mating with a male dog.
No
Sometimes.
doggy style. How did you think they do it?
Yes.
Yes but it has a better chance halfway through heat
Often, a male dog is protective of the pregnant female dog, usually if he is the "mate." Sometimes dogs, mates of the pregnant dog or not, will act aggressivley towards the female dog, also known as the "bitch."
She could die.
No