What is amniocentesis?

Amniocentesis is a prenatal diagnostic test done after 15 weeks of pregnancy to confirm if your baby has a genetic or other chromosome condition. This test is not offered to all pregnant women. Amniocentesis may help in making important decisions about your pregnancy. While some women are advised to have this procedure, the final decision to do so is yours.

Is an amniocentesis right for me?

Amniocentesis may be offered to you if:

• you have had a high risk prenatal screening test result
• you have already had a child with a genetic or chromosomal condition
• you are 35-37 years of age or over when your baby is due
• if both parents are carriers of a particular condition

Before you have the test it’s a good idea to think about why you are choosing to do it, and how you will feel once you get the results. Consider also who you want to discuss any important decisions with. Your partner, a friend or family member, or a health professional such as your doctor or midwife are all good options.

Can amniocentesis harm my baby?

There is a small risk of miscarriage with every pregnancy, having an amniocentesis may slightly increase that overall risk.

The risk of miscarriage after amniocentesis is estimated to be less than 1 in 200 pregnancies, although could be as low as 1 in 1000. Other than this, there are no known risks or complications to the pregnancy or baby from this procedure.

How is an amniocentesis performed?

Amniocentesis is performed by a specialist doctor in a hospital or specialist women’s ultrasound service.

The procedure involves inserting a very fine needle into your uterus (womb) through your abdomen to take a small sample of amniotic fluid that surrounds your baby.

The doctor will use an ultrasound to guide the needle, avoiding any contact with your baby. The procedure itself only takes a few minutes.

Your doctor will tell you if you need to do anything before the procedure, generally, you do not need to fast or do anything specific to prepare. You will be given local anaesthetic to numb the skin before the needle is inserted and will be awake for the procedure.

Who performs an amniocentesis?

Your doctor or midwife will refer you to a specialist obstetrician or obstetric imaging specialist.

You can use the Service Finder to find a specialist obstetrician near you. However, you will still need a referral from your health care provider for this procedure. .

How will I feel after the procedure?

Most women only experience minor discomfort, cramping and period like pain, during and after amniocentesis. The procedure itself only takes a few minutes, but you will most likely be asked to sit and rest in a waiting area for half an hour after the test before you go home.

If you have a negative blood group, an Anti-D injection would be given after the procedure.

You might experience some mild period-like pain on the first night after the procedure, but it is safe to use regular paracetamol if you need it.

If you have any vaginal bleeding, severe abdominal pain, high fever or unusual discharge from your vagina in the first week or two after the procedure, you should go to your nearest hospital emergency department.

When will I get the results of my amniocentesis?

Depending on your individual circumstance and the tests requested by the doctor performing the procedure, results of an amniocentesis may be available in 1 to 2 working days or up to 2 weeks. You can confirm when you will receive these results with your doctor.

How much does an amniocentesis cost?

Medicare will cover a proportion of the cost of the amniocentesis procedure, but there may be some other costs involved — for example, if you have a private obstetrician, there may be consultation fees for the procedure. Ask your doctor for more information about the costs involved in your specific circumstances.

More information

Your GP, obstetrician or midwife can answer your questions and give you more information on amniocentesis. They may also refer you to a genetic counsellor to help guide you through what your results may mean and decisions you may need to make. You might find it helpful to talk through how you may feel when you get your results, what it might mean for you and your family if you have a child with a genetic disorder, and what support will be available to you.