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Maternal Screen First Trimester

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Test Description
  • Contact: Maternal Screening (319) 335-4247. Interpretation or revised dating: UIHC OB/GYN Counseling (319) 356-8892.
  • Test Request Form: Maternal Screen First Trimester/Integrated
  • SHL OpenELIS Code: 855
Screen for Down Syndrome and Trisomy 18 risks in the first trimester of pregnancy. Does not include AFP for Open Neural Tube Defect (NTD) screening.
Performed Avg. Turnaround Time Method
Coralville, 8 a.m. - 5 p.m., M-F
3 - 5 business days Quantitative Chemiluminescent Immunoassay
Fee CPT Code(s)
$125.00 84163, 84702
Specimen Requirements
Specimen Type: Minimum 1 mL Serum
Patient Preparation: First trimester screening test for Down Syndrome and Trisomy 18, drawn between 10 weeks 0 days and 13 weeks 6 days gestation when Crown Rump Length (CRL) is 32-80 mm.
Collection Instructions: Dating by ultrasound Crown Rump Length (CRL). Serum sample drawn in the first trimester when the CRL is 32-80 mm. Incorrect dating will result in inaccurate risk assessment. Program brochures and patient consent forms are available for order.

Red Top Tube: centrifuge and transfer serum to a secondary tube.
    Serum Separator Tube: collect 4 - 6 mL and centrifuge.
        Shipping:
        Specimens should be stored and shipped under the same conditions. Wrap specimen container in absorbent material and place inside a biohazard bag. Transport specimen with cold pack. Ship to the Coralville location.
        Temperature and Stability: Refrigerated (2-8°C). Specimen must be received within 9 days of collection.
        Rejection Criteria: Specimens will be rejected if received under these conditions:

        Plasma. Samples not collected within the required gestational age range for the test requested. Specimens not received in the correct temperature ranges stated under "Temperature and Stability" will be rejected.
        Expected Results:
        MoM values for hCG and Papp-A; Risk Values for Down Syndrome and Trisomy 18; Screen Cutoff established for test; Interpretation/Recommended Action: Negative / No further action or Positive / Level II Ultrasound, counseling and consideration for diagnostic testing.
        Comments
        Incorrect information, especially incorrect dating, will result in inaccurate risk assessment. Requires Nuchal Translucency (NT) measurement by sonographer certified by FMF or NTQR. The sonographer's name, certification number, and certifying organization must be on file with the laboratory to submit an NT measurement. Call 319/335-4056 the first time a sonographer is submitting an NT measurement with a test request. If NT is unobtainable, order Maternal Screen Integrated Sample 1 test. The following information is required for test interpretation: Ultrasound date AND Crown Rump Length (CRL) measurement, an NT measurement obtained between 10 weeks 0 days and 13 weeks 6 days, patient's date of birth, current weight, patient's race, and, for IVF pregnancies, the age of the egg donor at time of egg retrieval. This test cannot be performed on multiples. Detection rates: 83% Down syndrome, 80% Trisomy 18. False Positive Rate: 5%. Note: if this test is performed, it is recommended that a Maternal Screen NTD be ordered in the second trimester.
        Alternate Names
        First Trimester Only (have required NT measurement and want a report in the 1st trimester for Down Syndrome and Trisomy 18)
        The University of Iowa

        State Hygienic Laboratory

        General inquires
        SHL Client Services
        319-335-4500 or 1-800-421-IOWA (4692)
        ask-shl@uiowa.edu

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