Maternal Serum Screen, Alpha Fetoprotein, hCG, Estriol, and Inhibin A (Quad)
Also known as: MS QUAD
Use
This test screens for fetal risk of Down syndrome (trisomy 21), trisomy 18, and open neural tube defects (ONTD, spina bifida). It is conducted during the second trimester and assesses the levels of several biochemical markers in maternal serum: alpha-fetoprotein (AFP), human chorionic gonadotropin (hCG), unconjugated estriol (uE3), and inhibin A. Abnormal levels of these markers can indicate an increased risk of chromosomal abnormalities or other fetal conditions.
Special Instructions
The serum should be drawn between 14 weeks, 0 days, and 24 weeks, 6 days of gestation, with the recommended time being 16 to 18 weeks. The test must include additional patient data like patient's date of birth, current weight, due date, dating method (ultrasound, menstrual estimation), number of fetuses, patient's race, family history of neural tube defects, and other pregnancy-related medical history.
Limitations
The test does not provide a definitive diagnosis but rather a risk assessment for certain fetal conditions. False positives and false negatives can occur, so abnormal results should be followed by further diagnostic testing, such as cell-free DNA (NIPT) or fetal diagnostic procedures. Additionally, certain factors like maternal weight, gestational age, and multiple gestations can affect the results.
New York Approved
Methodology
Immunoassay (CLIA)
Biomarkers
LOINC Codes
- 1834-1
- 11778-8
- 35738-4
- 23883-2
- 20450-3
- 49586-1
- 19151-0
- 21299-3
- 44877-9
- 8670-2
- 21484-1
- 11878-6
- 21612-7
- 2250-9
- 20466-9
- 32435-0
- 64234-8
- 11526-1
- 19080-1
- 20465-1
- 18185-9
- 29463-7
Result Turnaround Time
2-3 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
3 mL
Minimum Volume
1 mL
Container
Serum Separator Tube (SST) or Plain Red
Collection Instructions
Separate from cells ASAP or within 2 hours of collection. Transfer serum to an ARUP Standard Transport Tube.
Patient Preparation
Specimen must be drawn between 14 weeks, 0 days and 24 weeks, 6 days gestation. The recommended time for screening is 16 to 18 weeks gestation.
Storage Instructions
Refrigerated
Causes for Rejection
Plasma or hemolyzed specimens are unacceptable.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 72 hours |
| Refrigerated | 2 weeks |
| Frozen | 1 year (Avoid repeated freeze/thaw cycles) |