Being pro-life and pre-implantation diagnosis

The recent controversy over Peter Singer and Fordhman got me thinking about the logical implications of a consistent ethos. Singer certainly has a consistent ethos. Or at least he tries to work out the logical implications of his axioms, no matter where that goes. I don't agree with Peter Singer's utilitarianism because I am skeptical of his extreme ethical reductionism, but it's clarifying at least. But that got me to thinking about the implications of being pro-life in the 21st century, as biotechnology becomes more and more a part of our lives. From what I gather the standard pro-life position is that life begins at conception, where you have the potential for a human being. One aspect of this has always disturbed me: it is likely that more than 50% of conceptions miscarry, without anyone being the wiser. Most karyotype abnormalities, for example, miscarry. If these are human lives, does this mean that the majority of humans die even before they are born? How can we fix this tragedy? In the pre-modern age there wouldn't be a tragedy to fix. Saving these humans would be beyond our power. But today there are ways we may reduce the harm. First, one could fertilize a range of eggs, and then screen them for genetic abnormalities. Only the ones who pass a quality control threshold would be implanted, to minimize miscarriage risk.* The others could be put in 'stasis,' until the point where medical technology has advanced to the point that ailments can be fixed by genetic re-engineering at the zygotic stage. And that is my attempt to think like a pro-life Peter Singer. * In the future artificial wombs are definitely the way to go, as the developing fetus could be closely monitored.