Is it immoral,not to abort a fetus you knew would have down syndrome?

Would a pro-lifer adopt the baby and take on the challenge of having a child with mental impairment and probably physical problems as well? No. Would a pro-lifer contribute towards the additional costs of raising the child? No. No woman should be guilt-tripped into keeping a Downs syndrome child by such people.

It's never immoral to support life. Nature may not always be perfect, but it's not immoral to love your baby and make kid's life as good as possible.

that seems a rather selfish reason to take an innocent human life

It's immoral to kill babies. They feel pain and know they're being sliced up.

Hard question, but in life Nature would not allow people with such disabilities to survive.I see both sides of the argument

No, that's a choice you can make. Many choose to keep their child. Others don't.

No