The maternal serum screening (MSS) test is a blood test available to pregnant women in Victoria. It helps determine the chance of their unborn child having Down syndrome (trisomy 21), Edward syndrome (trisomy 18) or a neural tube defect.
Maternal serum screening may be done in the first trimester of pregnancy, when it is combined with an ultrasound. This is called the combined first trimester screening test. Or, testing may be performed in the second trimester of pregnancy. This is called the second trimester maternal serum screening test.
Also Known as: AFP Maternal, Maternal Serum AFP, MSAFP, msAFP, Triple Screen, Triple Test, Quad Screen, Quadruple Marker Test, 4-marker Screen, Multiple Marker Test
Formal Name: Maternal Serum Screen
Panel: Pregnancy, Preconception, First Trimester, Second Trimester, Third Trimester
Why Get Tested:
- The maternal serum screening test is a blood test offered to pregnant women.
- It helps to inform them of the chance of their unborn child having Down syndrome, Edward syndrome or a neural tube defect.
- The test may be performed at around 10 weeks (combined first trimester screening test) or between 14 and 20 weeks (second trimester maternal serum screening test).
- In most cases that are identified as ‘increased chance’, the baby does not have Down syndrome, Edward syndrome or a neural tube defect.
- Non-invasive pre-natal testing (NIPT) is a newer test that will inform nearly all pregnancies affected by Down syndrome, Edward syndrome and Patau syndrome.
When to Get Tested:
- Usually between the 15th and 20th weeks of pregnancy
- It helps to inform them of the chance of their unborn child having Down syndrome, Edward syndrome or a neural tube defect.
What is Being Tested:
In this screen, the biochemical markers measured in the mother’s blood are:
- Alpha feto-protein (AFP)
- Unconjugated estriol (uE3)
- Free beta human chorionic gonadotrophin (β-hCG)
- Inhibin A (DIA).
In Down syndrome pregnancies, the levels of these markers may be different. These results and your age are used to estimate your chances of having a baby with Down syndrome, Trisomy 18, Trisomy 13 and open neural tube defects.
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