Abortion -cpr on the fetus?

[Cato]

What is really being asked is at what stage of human development do we assign FSM (Full Moral Standing). The OP attempt to define this strictly in terms of viability. I agree with viability being a key element, but alone it is too simplistic (a theme I may take up later). Let's stick with viability. The other problem with using viability without a precise meaning immediately causes problems. Take for instance the OP's attempt to define viability strictly in terms of gestation length and establishing the lower bound by any one instance of survival. Based on this table, I don't think 20 or 21 weeks is a good measure of viability.