Test Code QUAD1 Quad Screen (Second Trimester) Maternal, Serum
Necessary Information
In order to provide the best results, either answer the order entry questions or provide the required information using the Second Trimester Maternal Screening Alpha-Fetoprotein / Quad Screen Patient Information (T595).
Specimen Required
Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 1 mL
Collection Instructions:
1. Do not collect specimen after amniocentesis as this could affect results.
2. Centrifuge and aliquot serum into plastic vial within 2 hours of collection
Additional Information:
1. For an assessment that includes neural tube defect results, gestational age must be between 15 weeks, 0 days and 22 weeks, 6 days.
2. Assessments for trisomy 21 (Down syndrome) and trisomy 18 (Edwards syndrome) only are available between 14 weeks, 0 days and 22 weeks, 6 days.
3. Initial or repeat testing is determined in the laboratory at the time of report and will be reported accordingly. To be considered a repeat test for the patient, the testing must be within the same pregnancy and trimester, with interpretable results for the same tests, and both tests are performed at Mayo Clinic.
4. Maternal Serum Screening patient education brochure (T522) is available upon request.
Specimen Type
SerumSpecimen Minimum Volume
0.75 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 7 days | |
Frozen | 90 days | ||
Ambient | 7 days |
Reject Due To
Gross hemolysis | Reject |
Gross lipemia | OK |
Gross icterus | OK |
Reference Values
NEURAL TUBE DEFECTS:
An alpha-fetoprotein (AFP) multiple of the median (MoM) <2.5 is reported as screen negative.
AFP MoM ≥2.5 (singleton and twin pregnancies) are reported as screen positive.
DOWN SYNDROME:
Calculated screen risks <1/270 are reported as screen negative, risks ≥1/270 are reported as screen positive.
TRISOMY 18:
Calculated screen risks <1/100 are reported as screen negative, risks ≥1/100 are reported as screen positive.
An interpretive report will be provided.
Day(s) Performed
Monday through Friday
Report Available
4 to 6 daysSpecimen Retention Time
14 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterCPT Code Information
81511