mbs: It would follow that the only thing wrong with the practice of eugenics, from a pro-choice point of view, is if it is socialized, or under the purview of the state. Privatized eugenics -- abortion for purposes of 'micro-managed' birth control, as it were -- should be perfectly all right, since prior to birth we are talking about living cells that are without personhood and thus disposable on the whim of other individuals.
Rather than ask what is a fetus, I might have asked instead, what is a baby less than, say, a day old? Or one that has lived in an incubator for a week? 'It' has no socialization to speak of. And if only socialization makes us human, then the baby is not human and has no rights.
I raise this not to suggest I have an answer that neatly resolves all of this, but to underscore the extent of intellectual arrogance that underlies the position that this question is so obvious as to preclude discussion.
mbs