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The following women can be referred for amniocentesis:
There are no absolute contraindications for amniocentesis.
Low risk pregnancy with risk of spontaneous abortion far outweighing the risk of a chromosomal abnormality.
Patients on heparin need to have this stopped before the test is performed.
There are three main risks which will be fully explained when the patient signs the consent form:
While amniocentesis is able to identify Down syndrome and genetic or inherited disorders, it needs to be noted that there are some chromosomal disorders for which there are no tests currently available.
Nuchal translucency in the first trimester is an ultrasound scan when, combined with maternal age and maternal serum levels of pregnancy hormones, can give us a risk ratio of the likelihood of Downs syndrome, trisomy 18 and trisomy 13. This is a statistical evaluation only and cannot definitively tell us an answer. It is only 85% accurate.
Chorionic villous sampling is done slightly earlier than amniocentesis and can examine the foetal DNA, which does not occur with amniocentesis. However, the risk of miscarriage is about 1% which is 2 -3 times higher than amniocentesis (see Chorionic Villous Sampling).
Page last modified on 29/3/2017.
RANZCR® is not aware that any person intends to act or rely upon the opinions, advices or information contained in this publication or of the manner in which it might be possible to do so. It issues no invitation to any person to act or rely upon such opinions, advices or information or any of them and it accepts no responsibility for any of them.
RANZCR® intends by this statement to exclude liability for any such opinions, advices or information. The content of this publication is not intended as a substitute for medical advice. It is designed to support, not replace, the relationship that exists between a patient and his/her doctor. Some of the tests and procedures included in this publication may not be available at all radiology providers.
RANZCR® recommends that any specific questions regarding any procedure be discussed with a person's family doctor or medical specialist. Whilst every effort is made to ensure the accuracy of the information contained in this publication, RANZCR®, its Board, officers and employees assume no responsibility for its content, use, or interpretation. Each person should rely on their own inquires before making decisions that touch their own interests.