I would modify this a bit. IMHO what's coming is designer genes. No fetus will need to be disposed of" because they'll be designed from the very beginning to conform to the parents' desires: boy or girl, tall or short, red or blonde or brown hair, blue or green or brown eyes, etc. And of course every single parent will ask for the genes to be inserted to insure athleticism, brilliance, and thinness (or at least to insure a very high metabolism so they'll be extremely unlikely to ever gain too much weight). To the extent possible, every parent will select genes insuring their kids grow up with attractive faces and bodies as well.
And you know what? In the unlikely event this happens soon enough for me to make such selections for my own children, I'll be first in line at Design-A-Kid. We live, sadly, in a world based on hate and bigotry, where those without the "proper" looks (and, coming very soon, without the proper genes) are almost always damned to a life in the slow lane, denied many of the most basic opportunities, finding many doors locked that always open for those that are "cute" and "sexy". Why would I want to risk having my kid go through a life of hell like that?
If society won't change and allow equality of opportunity (not of result), then I will absolutely take advantage of whatever science comes along that FORCES the playing field level. That's what conservatism is supposed to be about, after all.
No, you'll be in line behind the welfare crowd who will, naturally, get to design their kids "for free".
Hell exists in the mind and there's more than one kind of hell.
I'll stick with randomness or the will of God, so be it. Would we have had a Steven Hawking without some random quirk that produced such a severely handicapped person with such a magnificent intellect? What causes and effects produce genius in any field of endeavour? Would we end up designing a race of men that did nothing but admire their perfection in a mirror? Man's perfection is not in flawlessness but in his overcoming his weaknesses and faults. It is adversity that drives man forward. I think a perfect man in a perfect world would the weakest man of all.