Quadruple Marker, Serum

Quadruple marker screening is a blood test during pregnancy that tells if the fetus is at increased risk for having certain genetic disorders. A quad screen happens between 14 and 22.6 weeks of pregnancy. A quad screening doesn’t diagnose conditions — the results mean further testing may be necessary.

This test measures the blood levels of -details

1. AFP (alpha-fetoprotein) - This protein is produced by the fetal liver and is found in the mother’s blood. Abnormal levels of AFP can indicate potential issues with the fetus. High levels of AFP might suggest a neural tube defect, such as spina bifida, or abdominal wall defects. Low levels of AFP, on the other hand, can be associated with an increased risk of Down syndrome.
2. HCG (human chorionic gonadotropin)- hCG stands for Human Chorionic Gonadotropin. This hormone, produced by the placenta during pregnancy, plays a critical role in maintaining the pregnancy. In the context of the quadruple marker test, hCG provides important information about the health of the fetus and can help assess the risk of certain conditions.
3. Estriol (a form of estrogen)- Measuring uE3, along with the other markers in the test, helps assess the risk of certain fetal conditions.
4. Inhibin-A- Elevated levels of Inhibin A are associated with an increased risk of Down syndrome (Trisomy 21).

The quad screen looks at four substances in your blood. Abnormal levels of these substances (either too much or not enough) tell your provider that the fetus may be at risk for having a genetic disorder. Some of those disorders include:

• Trisomy 21 (Down syndrome)
• Trisomy 18 (Edwards syndrome)
• Neural tube defects (NTDs)

This test can be done during 14 - 22.6 of gestational age only. Blood sample is provided along with the latest USG report with other important details like weight, date of birth, date of collection, maternal race, History- smoking, diabetes, IVF and all common aneuploidy.

• The test is recommended for mothers who are pregnant at an advanced age or depending on the age of the egg donor
• It is recommended if there is a family history of genetic problems or chromosomal abnormalities
• The test is recommended for pregnant women who have previously screened positive for chromosomal abnormalities in previous pregnancies
• The test is recommended for those whose dual marker screening tests may have come ambiguous or at a certain risk.

Multiple marker serum screening has become a standard tool used in obstetrical care to identify pregnancies that may have an increased risk for certain birth defects, including neural tube defects (NTD), trisomy 21 (Down syndrome), and trisomy 18 (Edwards syndrome). The screen is performed by measuring analytes in maternal serum that are produced by the fetus and the placenta. The analytes that are measured in triple test include AFP (Alpha fetoprotein), HCG (Human chorionic gonadotropin), UE3 (Unconjugated Estriol) and Inhibin A. The analyte values along with maternal demographic information such as age, weight, gestational age, diabetic status, and race are used together in a mathematical model to derive a risk estimate.

The laboratory establishes a specific cutoff for each condition, which classifies each screen as either screen-positive or screen-negative. A screen-positive result indicates that the value obtained exceeds the established cutoff. This test is a screening test, a positive screen does not provide a diagnosis, but indicates that further evaluation/genetic counseling should be considered.

Incorrect or incomplete information may significantly alter results. Risks are adjusted for donor eggs, frozen embryos, and IVF. Results may be unreliable in twin pregnancies with a fetal demise. Results are not available for pregnancies with triplets and higher-order multiples.

Other names: Quadruple Test, Quad screen