Triple Marker with Graph
What is Triple Marker with Graph?
A triple marker test is done in pregnant women to detect any abnormalities in the fetus before birth. The triple marker with graph test is also known as the Triple test, multiple marker test, multiple marker screening, and AFP plus test.
This test measures three markers in the blood:
Human chorionic gonadotropin (HCG)
Why is Triple Marker with Graph done?
To diagnose Down syndrome
To diagnose neural tube defects
To diagnose the failure of closure of the abdomen in the fetus.
To diagnose multiple pregnancies
To diagnose miscarriage or ectopic pregnancy
What does Triple Marker with Graph Measure?
This test measures three markers which include AFP, HCG, and estriol in the blood. As there are three markers involved, it is known as the Triple Marker test.
AFP is a protein which is produced by the fetus. If the levels of AFP are high, it indicates neural tube defects in the fetus or there can be incomplete closure of the fetus abdomen.
HCG hormone is produced by cells of the placenta. If the levels of HCG are low, it indicates a miscarriage or ectopic pregnancy. Whereas, if the levels of HCG are high this indicates multiple pregnancies.
Estriol is a form of the hormone estrogen which is present in both fetus and placenta. If the levels of estriol are low, it indicates the risk of the baby getting delivered with Down syndrome especially when the levels of AFP are low and HCG are high.
If the levels of all these three markers are abnormal, there can be a presence of neural tube defects like spina bifida (spinal cord fails to develop properly), anencephaly (absence of brain, skull, and scalp), and multiple pregnancies (twins or triplets).
This test is done between 15-20 weeks of pregnancy. Females who are 35 years or more, have a family history of birth defects, or have diabetes or are using insulin have a higher risk of getting abnormal values of these markers. Exposure to high levels of radiation or having the viral infection during pregnancy can also be considered as possible risk factors associated with these high levels. This test is also helpful to indicate any complications in the fetus after birth.
Interpreting Triple Marker with Graph results
False positive rate
Neural tube defects
≥ 2.5 MoM (Multiples of median)
Down Syndrome (Trisomy 21)
Edwards Syndrome (Trisomy 18)
The base of screening tests is a statistical analysis of patient’s data which includes the demographic (statistical study of populations) and biochemical (laboratory) data.
Confirmation is mandatory by amniocentesis.
The results are illustrated in the form of a graph in the test report.