Triple Marker with Graph (2nd Trimester)
Understanding Triple Marker with Graph (2nd Trimester)
What is Triple Marker with Graph (2nd Trimester)?
Triple Marker with Graph is a maternal screening test which provides useful information about pregnancy. This test is done during 15-20 weeks of pregnancy to assess and screen the fetus for certain birth defects. The test measures the level of three important markers in the blood, Alpha-fetoprotein (AFP), Human chorionic gonadotropin (HCG), and Estriol.
The triple marker is a blood test which helps diagnose genetic disorders like Down and Edward syndrome and neural tube defects. It is also useful in identifying ectopic pregnancy, miscarriages, and multiple pregnancies. .
In case of abnormal results, an amniocentesis test may be advised and sometimes a detailed ultrasound is also done to examine the fetal skull and spine.
What is Triple Marker with Graph (2nd Trimester) used for?
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 (2nd Trimester) 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 (2nd Trimester) results
Interpretations
Pregnancy Weeks | AFP | HCG | Estriol |
15 | 32.01 ng/mL | 32200 mIU/mL | 0.55 ng/mL |
16 | 37.67 ng/mL | 25690 mIU/mL | 0.76 ng/mL |
17 | 44.33 ng/mL | 20490 mIU/mL | 1.00 ng/mL |
18 | 52.16 ng/mL | 16340 mIU/mL | 1.25 ng/mL |
19 | 61.38 ng/mL | 13040 mIU/mL | 1.50 ng/mL |
20 | 72.33 ng/mL | 10400 mIU/mL | 1.76 ng/mL |
Abnormality | Cut off | Detection rate | False positive rate |
Neural tube defects | ≥ 2.5 MoM (Multiples of median) | 70-75 % | 2-4 % |
Down Syndrome (Trisomy 21) | 1: 250 | 65 % | 5 % |
Edwards Syndrome (Trisomy 18) | 1:100 | 60 % | 0.3 % |
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.