16 to 22 Weeks of Pregnancy
Click on a question to take you to the answer.
What is the Quadruple Down Sydrome Test?
How does the Quadruple Down Dyndrome Test work?
What other information is required to complete the Quadruple Test?
Why is it called the Quadruple Test?
When will I get the result of my Quadruple Down Sydrome Test?
What is meant by a Screen-Positive result?
How accurate is the Quadruple Down Syndrome Test?
What are the risks of the Quadruple Down Sydrome Test?
Are there any limitations to the Quadruple Down Sydrome Test?
Can the Quadruple Test be performed on twins?
Can other abnormalities be identified by the Quadruple Test?
What's the alternative to the Quadruple Test?
Where can I read more about the Quadruple Down Syndrome Test?
What is my next scan after the Quadruple Down Syndrome Test?
How do I book a Quadruple Down Syndrome Test?
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What is the Quadruple Down Syndrome Test?
The Quadruple Test is a screening for Down Syndrome and is usually performed if you have missed the Nuchal Scan or Integrated Test earlier in your pregnancy.
If you have already had the combined Nuchal Scan or Integrated Test and have received a risk result that concerns you with we strongly suggest that you consider a diagnostic test like a CVS or Amniocenteses rather than undertake another different screening like the Quadruple or Integrated tests.
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How does the Quadruple Down Syndrome Test work?
To complete the Quadruple Test first we must accurately date your pregnancy by performing a scan. Please note that we cannot use dating information from any previous scans that you may have had with this pregnancy.
We then ask you some detailed questions about your pregnancy before taking a blood sample and sending the sample to the laboratory for analysis.
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What other information is required to complete the Quadruple Test?
We need to know the following details to sucessfully perform the test:
- First day of last Menstrual Period? (LMP)
- Maternal Weight? (we have scales)
- Ethnic Origin of the Mother?
- Are you Insulin Dependent?
- Date of Birth of donor? (if an IVF pregnancy)
- Are you a smoker?
- Are you taking Folic Acid?
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Why is it called the Quadruple Test?
It is called the Quadruple Test because it measures four substances in your blood to calculate a Down Syndrome risk result:
- AFP
- Beta HCG
- Inhibin-A
- Oestriol
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When will I get the result of my Quadruple Down Syndrome Test?
We usually receive the result in 4 working days although occasionally it can take longer depending on the laboratory backlog.
We will call you with the outcome of the test and email you a copy of the report.
In the report you will receive a risk estimate similar to other Down Syndrome screenings such as the Nuchal Scan or Integrated Test. A high risk result will be identified as Screen-Positive.
If you and your partner are not reassured by the final risk estimate you have the option of having an Amniocentesis at The London Ultrasound Centre to obtain a definite result.
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What is meant by a Screen-Positive result?
A Screen-Positive indication will be given where the result of your Quadruple Down Syndrome test has passed a certain threshold.
The UK National Screening Committee has defined a 1:200 risk at birth as the screen-positive level for the Quadruple Test.
If your result is 1:200 or higher risk you will be offered a diagnostic test, in this case an Amniocentesis.
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How accurate is the Quadruple Down Syndrome Test?
Data from the Wolfson Institute has shown that in screening for Down Syndrome the Quadruple Test achieves a detection rate of 78%. (A detection rate is the number of babies with Down Syndrome predicted by a positive test.) Note that 22% of women with pregnancies affected with Down's syndrome will receive a (falsly reassuring) screen-negative result.
The test achieves the detection rate with a screen positive rate of 3%, that is the number of babies who did not have Down’s Syndrome but were considered high risk by the test. Therefore 97% of women whose pregnancies are not affected with Down's syndrome will receive a screen-negative result.
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What are the risks of the Quadruple Down Sydrome Test?
The test is not dangerous and will not harm you or your baby.
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Are there any limitations to the Quadruple Down Syndrome Test?
Yes.
- The Quadruple Test can only be performed between 16 and 22 weeks of your pregnancy
- The Quadruple Test cannot be performed if you are an insulin dependent diabetic
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Can the Quadruple Test be performed on twins?
Yes, although screening in twin pregnancies poses a difficulty because of the possibility that one fetus may be affected and the other may not.
For this reason the Quadruple Test is only able to provide and overall risk for the pregnancy and not for each individual baby.
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Can other abnormalities be identified by the Quadruple Test?
Yes. A high AFP level from the Quadruple Test may also alert the sonographer to look even more carefully for Spina Bifida at the 18-20 week anomaly scan (but will not positively identify Spina Bifida).
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What's the alternative to having a Quadruple Down Syndrome Test?
An alternative is to have a detailed scan performed by one of our highly qualified Consultants or Sonographers around the middle of your pregnancy where they will look for 'markers' for Down Syndrome and Spina Bifida.
To obtain an absolute answer you may decide to have the Amniocentesis diagnostic test.
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Where can I read more about the Quadruple Down Syndrome Test?
For copies of the Quadruple Test information leaflets from the Woolfson Institute (the laboratory) please click on the links below.
The documents are provided in PDF format.
The Quadruple Test | Questions
and Answers for patients
The Quadruple Test | Information for Healthcare Professionals
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What is my next scan after the Quadruple Test?
The next scan you should expect in your pregnancy after the Integrated Test is the Anomaly Scan at 20 weeks.
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How do I book a Quadruple Down Syndrome Test?
For prices and to make a booking please see our online booking website.
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