Hi

I am writing on behalf of my sister who is currently living in Spain.
She recently had a 12wk scan combined with a 14wk bloodtest which came back 'High risk' for Down syndrome - I pressume.
She is reluctant to have an amnio, wishes she didn't have the test etc.
Does anyone have advice about the testing process and how they derive this rating?
ie. accuracy?

She has had one healthy child already in Australia with no complications etc.

Thank you.