What is a Triple marker screen test?
The triple marker screen test is also known as the triple test, as the name indicates three markers are tested in the maternal bloodand compared to a baseline and interpretation is drawn .it is Done at 16 weeks but can be done between 15-20weeks
The markers are
- Alpha-fetoprotein (AFP)
- Human chorionic gonadotropin (HCG)
- Estriol
What does a triple marker screen test do?
AFP: A protein produced by the fetus. High levels of this protein can indicate neural tube defects. or abdominal wall defects.
hGC: A hormone produced by the placenta. Low levels may indicate potential problems with the pregnancy, including possible miscarriage or ectopic pregnancy. High levels of HGC can indicate a molar pregnancy, or a multiple pregnancy like twins and triplets.
Estriol: An estrogen that comes from both the fetus and the placenta. Low estriol levels may indicate risk of having a baby with Down syndrome, especially when paired with low AFP levels and high HGC levels.
Abnormal levels
Abnormal levels of these substances may indicate the presence of:
- Neural tube defects, such as spina bifida and anencephaly
- Multiple infants, such as twins or triplets
Abnormal levels can also indicate Down syndrome or Edwards syndrome. Down syndrome occurs when the fetus develops an extra copy of chromosome 21. Edwards syndrome(Trisomy 18) can result in extensive medical complications. Only 50 percent of fetuses with this condition survive to birth.
Who benefits from the triple marker screen test?
Triple marker screen tests help to screen pregnancy as a routine.
The test is often most recommended for women who:
- 35 years old or older
- A family history of birth defects
- History of diabetes and use insulin
- Exposure to high levels of radiation
- Exposure to viral infection during pregnancy
Other factors that can affect the test results
- The mother’s weight
- Ethnicity
- Age
- Diabetes
- Gestational agewhether or not she’s having a multiple pregnancy
The quadruple marker test
It’s a blood test done in second trimester screening test — is a prenatal test and measures levels of four substances in pregnant women’s blood:
- Alpha-fetoprotein (AFP), a protein made by the developing baby
- Human chorionic gonadotropin (HCG), a hormone made by the placenta
- Estriol, a hormone made by the placenta and the baby’s liver
- Inhibin A, another hormone made by the placenta
Ideally, the quad screen is done between weeks 15 and 18 of pregnancy — during the second trimester. However, the procedure can be done up to week 22.