I take great pride in the fact that I never have had a child. Given my very strong view points on the population problem, it's not hard to figure out why.
My point is, you said you never wanted children. I've never taken an illegal drug, but it's not something I ever wanted to do, so there's no reason why I would be proud of it. Now, if someone refrains, for ethical reasons, from doing something they desperately want to do, they would have cause to be proud of the self control they exercised.
In response to the OP question, I have no biological children, by choice.