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Second Trimester Screen

Item Value
Approval req'd? No
Available Stat? No
Test code STS
Test group Prenatal screening
Performed by Western Clinical Laboratories, Inc.
Sendout? Yes
Patient Preparation Have the patient read the Program booklet and sign the consent form. The consent is to remain with the clinic.
Collection Instructions Prior to collection:
Send the remainder of the Program form with the patient to have the sample collected between 15 weeks to 20 weeks of pregnancy (Second Trimester). Include a completed Routine Laboratory requisition listing 'Second Trimester Screen' in the lower right corner of the form.

To allow correct billing, provide Medi-Cal information, if applicable. Otherwise, enclose a copy of insurance card.

At the time of collection:
Complete Part B (green) at the bottom of form.

Draw the patient's blood using the 3.5 mL serum separator tube supplied in the program kit.

Apply the white collection label from the top of this page to the tube with the patient's name and collection date.
Container type Special SST supplied in Prenatal Screening test kit.
Amount to Collect 3.5 mL blood
Sample type Serum is used for testing but the entire unopened tube must be sent.
Preferred volume 3.5 mL blood (1.5 mL serum)
Min. Volume 3.5 mL blood (1.5 mL serum)
Processing notes Let whole blood stand for 1/2 hour to 1 hour after time of collection before centrifuging to aid clot formation. Centrifuge tube and place the centrifuged tube in the blue plastic tray i Place plastic tray in the absorbent pouch. Seal the pouch.

Place the white copy of the completed form, the insurance information in the red mailing box.

Remove the Business Reply label from the top of the form and place it on the red box, mail the same day, if possible.

If specimen is sent by courier, follow the courier's instructions for packaging.
Ref Lab Rejection Criteria 1. No information on tube or in package containing the tube
2. Specimen arrives with no test request form (TRF)
3. Tube arrives damaged or broken
4. Quantity of serum is insufficient for analysis
5. Specimen arrives hemolyzed
6. Specimen arrives over 30 days (1st trimester) or 10 days (2nd trimester) after blood collection date (1st trimester)
7. EDTA contamination in tube
8. 1st trimester specimen is not properly centrifuged
- Let whole blood stand 1/h hr to 1 hr before centrifuging to aid clot formation.
- Centrifuge at 1000 x g for minimum of 10 minutes.
9. TRF number on TRF does not match TRF number on tube
10. Patient last name on tube does not match spelling of patient last name on TRF
11. Patient last name or TRF number is absent from either tube or TRF
12. Different middle initials on tube vs TRF
Normal range
Synonyms Triple screen; Obstetrical screen; Down's syndrome screen; Neural tube defect screen; Alpha-fetoprotein; alpha-fetoglobulin; AFP3; E3; Expanded AFP screening; Maternal serum screen; MSS3; Triple screen; Maternal tests; Prenatal screening
Turn around times 10 days from time of receipt at Western Clinical laboratories
Additional information For questions, call the California Prenatal Screening Program at (866) 718-7915 Toll Free.
CPT coding The Prenatal Screening Billing Code is assigned by the Program upon request.
Last Updated 3/22/2013 12:55:11 PM
Entry Number 1218
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