Perhaps there is a particular gene in you that might save humanity from a particular disease in future but due to your mindset, you refused to pass this gene to the subsequent generation? You have totally erased your gene from the gene pool without you thinking of it.

Why do you say I never thought of it?
Maybe I thought about that, but I just don't care about future generations? I don't feel any responsibility for the people who are alive while I'm dead. Why should I?

In addition to that: it's probably one of the worst reasons to get children at all. In my case it would be like "Look, I don't like you and I don't want you - but since I got told you might be humanities last hope, I'm stuck with you. And now stop whining and finish breakfast."

I would be such a loving father. Not.