90%

The New York Times reports on a grass roots effort by parents of children with Down syndrome to educate obstetricians and other prenatal counselors on the value of their children's lives.  The article reports that 90% of pregnant women who are given a Down syndrome diagnosis choose to have an abortion.  While the reporter acknowledges some nuance to the issue, she appears to presume that the parents are motivated simply by concern for their own children:

The parent evangelists are driven by a deep-seated fear for their children’s well-being in a world where there are fewer people like them. But as prenatal tests become available for a range of other perceived genetic imperfections, they may also be heralding a broader cultural skirmish over where to draw the line between preventing disability and accepting human diversity. . . .

A dwindling Down syndrome population, which now stands at about 350,000, could mean less institutional support and reduced funds for medical research. It could also mean a lonelier world for those who remain.

This is undoubtedly the motivation for many parents.  But the experience of Down syndrome parents, I imagine, could also drive them to speak on behalf of unborn children with Down syndrome not as statistics for increased lobbying leverage, but as lives of value, period.

We are just seeing the tip of the iceberg, of course.  The London Times reported on Sunday that fertility clinics in the UK have received permission to begin screening embryos for "severe cosmetic conditions."