She probably wont be able to have the test done again as it's a time specific test. If she's worried about the result then she needs to think about having an amnio or CVS. Amnio has 1/2 the risk of m/c than what CVS does. Despite already having had 3 miscarriages I went ahead with the amnio as my risk of having a m/c was way less than my risk of having a DS bub was (1/37).

The test she's had done is not a diagnostic test - it only gives a risk factor therefore there's no such thing as accuracy as such. A result of 1/220 means that out of 220 women with the exact same results as hers one will have a DS baby & 219 will not. The test cannot say which of the women will be the one to have the DS baby. The only way of knowing if it's DS or another trisomy is to have the amnio or cvs.

I found the amnio itself to be no big deal - no worse than having any blood test done.... no pain, but the wait afterwards to see if you will m/c or have a bad result is really bad, but probably easier than spending the rest of the pregnancy worrying about it.