Maternal Screening, Sequential, Specimen #1, hCG, PAPP-A, NT
Also known as: MS SEQ1
Use
This test is used in the first trimester to screen for trisomy 21 (Down syndrome) and trisomy 18. It requires a nuchal translucency measurement performed by an ultrasonographer certified by the Fetal Medicine Foundation (FMF). The test provides a risk assessment for chromosomal abnormalities early in pregnancy, allowing for informed clinical decisions and possible follow-up diagnostic testing.
Special Instructions
Specimen must be drawn between 11 weeks, 0 days and 13 weeks, 6 days of gestation. Necessary information such as the patient's date of birth, current weight, number of fetuses, race, and other pregnancy-related factors should be submitted with the order. Contact a genetic counselor at 800-242-2787 ext. 2141 for coordination if the ultrasonographer is new to the ARUP database.
Limitations
The test is a screening tool and not diagnostic. It is dependent on accurate gestational dating, proper sample collection, and certified nuchal translucency measurement. Issues such as unknown race, incorrect gestational age, or missing sonographer certification may affect risk calculations or result interpretations. Follow-up with diagnostic testing such as cell-free DNA (NIPT) or fetal diagnostic testing is suggested for positive screens.
New York Approved
Methodology
Immunoassay (CLIA)
Biomarkers
LOINC Codes
- 49586-1
- 19151-0
- 21484-1
- 11878-6
- 21612-7
- 12146-7
- 32123-2
- 49089-6
- 49088-8
- 34970-4
- 49035-9
- 32435-0
- 33882-2
- 48407-1
- 64234-8
- 11957-8
- 11526-1
- 19080-1
- 20465-1
- 18185-9
- 29463-7
- 12146-7
- 49035-9
Result Turnaround Time
2-4 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 and transfer to an ARUP standard transport tube.
Patient Preparation
None specified for fasting or other preparations; patient-specific data required for accurate results.
Storage Instructions
Refrigerated.
Causes for Rejection
Plasma. Hemolyzed specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 72 hours |
| Refrigerated | 2 weeks |
| Frozen | 1 year (Avoid repeated freeze/thaw cycles.) |