Amniocentesis is a test carried out during pregnancy,
which is used to detect possible abnormalities in the unborn child.
It is used to test for two main things:
- Chromosomal disorders such as Down's syndrome.
- To see whether the baby's lungs are mature or
However it can also be used to test for a number
of other congenital defects such as spina bifida. Amniocentesis can also find
out the sex of an unborn baby.
happens during amniocentesis?
The doctor inserts a very fine and hollow needle
into the womb. An ultrasound is used to map the position of the placenta and
guide the needle.
The needle removes 20mls of amniotic fluid from
the womb. (Amniotic fluid is the fluid which surrounds a foetus in the womb.)
This fluid contains some of the baby's cells and
is sent to a laboratory for analysis.
The mother may feel some discomfort but the procedure
only lasts five to 10 minutes. Some women may experience minor cramping after
the procedure. Amniocentesis does not hurt the baby.
Generally amniocentesis is a safe procedure with
no complications. However as with any other procedure, it is not completely
There is a very slight chance that amniocentesis
will cause a miscarriage (0.5 to 1%). Because of this, you will probably only
be offered an amniocentesis if you are at higher risk of having a child with
abnormalities. You may wish to have it if:
- You are over 35.
- There is a history of chromosomal disorders,
such as Down's syndrome in your family.
- There is a history of chromosomal disorders
in your partner's family.
long do the results take?
The final results can take up to three weeks. In
some cases, preliminary results are available
reliable are the results?
The results of amniocentesis are extremely reliable.
The procedure is 99.9% accurate in identifying chromosome abnormalities.
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