Hey math people,
Take this assumption as correct (it's required for the question to make any sense): "For a stable population, a woman (or family couple) need to statistically have at an average 2.1 children."

Question- If you have in any way rendered yourself not capable of having children - How many lives at an average rate, would you need to save, in order for you to make up for the above 2.1 offspring requirement?

(Please assume all saved individuals will be a default person who will go on to have children of their own.)