Frequently asked questions
1
How accurate is it?
This test has shown to be more than 99% accurate in identifying pregnancies
affected with Down syndrome (trisomy 21) (less than 1 out of 200 pregnancies with
Down syndrome will not be identified by this test), 97% of pregnancies with Edwards
syndrome (3 out of 100 pregnancies with Edwards syndrome will not be detected)
and 87% of cases of Patau syndrome (13 out of 100 cases will not be detected on
this test).
2
What does the test look for? Is it everything?
The test only looks at chromosomes 13, 18 and 21. These are the most common
chromosome abnormalities that can occur in pregnancies. Only extra copies of these
chromosomes will be detected. Any other genetic conditions or abnormalities will not
be identified.
3
How will I get the results?
You will receive your result by post. If you have a high risk result we will telephone
you directly to discuss the result with you.
4
Will this change my routine care?
No, you will carry on having your routine NHS care as per any other pregnant
woman.
5
What happens if I get an increased risk result?
This does not mean that your pregnancy is definitely affected with a trisomy; there is
a small risk that the result is incorrect. You will be offered an invasive test such as a
CVS or amniocentesis which will be able to check the chromosomes of the
pregnancy. These invasive tests will give a definite result.
6
I have been asked for a repeat sample; does this mean my pregnancy is
affected?
No, it just means that the sample did not have enough fetal DNA to be able to carry
out the testing. This happens very rarely, you will not be charged for this extra
sample.
7
What happens if my second sample doesn’t work?
Unfortunately in some women a result is never obtained. This occurs in a small
number of cases. If a second sample does not produce a result, then it is unlikely
that a result will be available with another blood sample. In these cases you will not
receive a refund.
8
I have a low result; this means that my pregnancy is not affected?
It is very unlikely that your pregnancy is affected with a trisomy if you have been
given a low risk result. However, as mentioned above, there is a small chance that
the test will not pick up all trisomy pregnancies.
9
Who can have the test?
Any woman with a singleton pregnancy can have the test. Women who are pregnant
from donor eggs can also be offered this test.
10
Can I have the test at another hospital?
This test is currently offered as a private additional test at Birmingham Women’s
Hospital. There are other hospitals offering this test in the West Midlands
11
Is there any risk to my baby by having this test?
No as the test is carried out on a blood sample from you, there is no harm to the
pregnancy.
12
At what stage in the pregnancy can I have the test? It is more accurate if
done earlier in pregnancy?
The test is available from 10 completed weeks into a pregnancy. It can be carried out
at any stage on the pregnancy after 10 weeks as prior to that time, there may not be
enough fetal DNA circulating in Mum’s blood stream to carry out the test.