What is amniocentesis?

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:

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.

What 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.

Does amniocentesis hurt?

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.

Is amniocentesis safe?

Generally amniocentesis is a safe procedure with no complications. However as with any other procedure, it is not completely risk-free.

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:

How long do the results take?

The final results can take up to three weeks. In some cases, preliminary results are available sooner.

How 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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