Keep the baby with risk of genetic disorder or abortion?

Are such disorders inherited?
If they're not, and a child MIGHT only inherit a slightly increased tendency to develop the disorder, then there's no reason to go against what you believe. Assuming that sex was consensual of course - if the person raped you, or hurt you against your will in any way, then maybe you'd never be able to bring the child up anyway, so you'd need to either have it adopted, or abort it.

Don't forget that most people are truly shocked to find that their offspring has such a condition - it certainly can't run in such families to the extent that they could have assumed their child would have it!

And above all, remember that even the most perfect couple in the world, with pristine and sanctified family medical histories, can STILL have a child with a major defect.