Boombox695
Neon Wasteland
There's also the case of incest. A child born out of incest can have multiple medical problems.
Any increase in the chance of birth defects is negligible for the first two generations, IIRC.
Truth. I believe, but cannot say for certain that, a birth defect is more likely to occur do to damaged(read as: old, crusty) ova then as a result of incest.
But even so, anyone with a moral opposition to abortion is harbouring a great heap of poppycock and is advised to seek out cognitive enhancement.