Hi, I posted on your previous thread, I'm so sorry hear your news.
My heart goes out to you, it's a difficult decision you have to make.
Around 95% of people who have amnio/cvs and discover that the baby has Down or another trisomy, do terminate the pregnancy (people who are very against termination tend not to have the diagnostic tests).
My pregnancy was very high risk, and we would have chosen a termination, having already discussed all the different aspects - including the effects on our other children, and the affected child too- we are in our 40's and in the case of Down, people with this condition, with good medical care, can live into their 50's even 60's now, so what happens when we are gone?
The head and the heart may say different things to you - but there is not just the baby to consider, or the child, but also the adult, and the particular needs they will have in the years to come. Research all that, get as much information as you can.
Whatever you decide, you need to be sure it's right for you. Whatever you decide, WILL be right for you.
I don't know if you can think about the future or another child at the moment, and maybe this is hideously insensitive,
but if you choose to try for another child, as you are having IVF anyway, you may be a good candidate for PGD (the cells of the embryos can be checked before implantation).
I'm sorry if that comes across as callous, I don't mean it to be. wither you choose to continue with this pregnancy or not, you may want to have another child in the future and I just mean that you can use PGD to avoid the risk of an affected baby next time.
I wish you well with your decision making.