Do you mean when the Bad Egg hatches and breeds with another Pokemon, would the offspring be a Bad Egg?
Well, firstly, the only way to get a Bad Egg is through hacking.
Secondly, Bad Eggs never really hatch.
Thirdly, in the rare case a Bad Egg hatches, the game would automatically freeze.
So... yeah. I hope that answers your question, in one way or another. xD