I don't find abortion mentioned often in HBD writing, except occasionally in the context of sex-selection or speculations about selecting for other traits at some future date. If I had to guess, I would say that few of that crowd are strongly pro-life, simply because 1) it's never mentioned and 2) there is a slightly lesser percentage of religious people, and Catholics and Evangelicals make up most of the strong pro-lifers.
It is interesting then, that they are coming to a very Catholic position in one small part of the discussion: who you are is very much more determined at conception than the rest of the culture believes. I don't know what comes of it. Perhaps nothing. But it's interesting.