Chorionic Villus Sampling (CVS test)
This
is a diagnostic test that’s widely available if your first trimester screening
indicates your baby may have a chromosomal disorder such as Down syndrome.
It may also be offered to
women who are over 35 or who have a family risk of
inherited disorders. Because there’s a risk of miscarriage after this procedure (between
0.5% and 2%), any woman considering this test ought to think very carefully
before going ahead with it. It may help you to ask your OB-GYN what the
hospital’s miscarriage rate is after such a procedure.
The
test itself is carried out at 10-13 weeks and is fairly straightforward. It
involves taking a sample of the placental via a fine needle inserted through
your abdomen. An ultrasound scan is used to establish where the
placenta is lying in your uterus, and monitors your baby’s position during the
test. Placental tissue has exactly the same genetic code, or DNA, as your
unborn baby – and this means that if your baby has Down syndrome or another
chromosomal disorder, the placenta will reveal it.
The information in this feature is intended for
educational purposes only. If you have any concerns about your health, the
health of your child or the health of someone you know, please consult with a
doctor or other healthcare professional.
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