Maternal Serum Screening, Integrated, Specimen #2, Alpha Fetoprotein, hCG, Estriol, and Inhibin A
Use
The Maternal Serum Screening Integrated Test provides risk assessments for open neural tube defects, Down syndrome (trisomy 21), and trisomy 18 by analyzing maternal serum markers. This screening involves the measurement of alpha-fetoprotein (AFP), human chorionic gonadotropin (hCG), estriol, and inhibin A. The test is part of a two-step process, with the first specimen typically taken in the first trimester and this second specimen taken between 14 to 24 weeks of gestation. By integrating results from both specimens, it offers a comprehensive evaluation that can guide further diagnostic testing or intervention.
Special Instructions
Not provided.
Limitations
Despite comprehensive screening, a result indicating "normal" may miss 15% of Down syndrome cases, 20% of open neural tube defects, and 10% of trisomy 18 cases. Abnormal results necessitate follow-up procedures, including targeted ultrasound and potential fetal diagnostic testing. It is crucial that the second specimen for sequential screening is received, as failure to do so will render the results uninterpretable, preventing any assessment of maternal risk.
Methodology
Immunoassay (CLIA)
Biomarkers
LOINC Codes
- 1834-1 - AFP SerPl-mCnc
- 20450-3 - AFP MoM SerPl
- 2250-9 - u Estriol SerPl-mCnc
- 20466-9 - u Estriol MoM SerPl
- 19080-1 - HCG SerPl-aCnc
- 20465-1 - HCG MoM SerPl
- 23883-2 - Inhibin A SerPl-mCnc
- 35738-4 - Inhibin A MoM SerPl
- 32046-5 - PAPP-A SerPl-aCnc
- 32123-2 - PAPP-A MoM SerPl
- 12146-7 - Fet Nuchal fold Thickness US.meas
- 49035-9 - Fet Nuchal fold MoM Thickness US.meas
- 49586-1 - Integrated scn Patient-Imp
- 21612-7 - Age - Reported
- 29463-7 - Weight
- 11778-8 - Deliv date Clin est
- 18185-9 - GA
- 21299-3 - GA method
- 11878-6 - # Fetuses US
- 21484-1 - Mother's race
- 44877-9 - IDDM Patient Ql
- 64234-8 - Current smoker
- 8670-2 - Family member diseases Hx
- 32435-0 - Hx of Hereditary disorders
- 19151-0 - Specimen drawn SerPl
- 11957-8 - Fet CRL US.meas
- 49089-6 - Sonographer
- 49088-8 - Sonographer name
- 34970-4 - US Date
- 11526-1 - Pathology study
Result Turnaround Time
2-8 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
3 mL
Minimum Volume
1 mL
Container
Plastic vial
Collection Instructions
As soon as possible or within 2 hours of collection, centrifuge and aliquot serum into a plastic vial. Send refrigerate.
Causes for Rejection
Hemolysis, Plasma
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 72 hours |
| Refrigerated | 14 days |
| Frozen | 365 days |
