Test Catalog

Test Name

Maternal Screening - Sonographer Approval Process

Test ID: 1STT - First Trimester Maternal Screen
Test ID: SEQU - Sequential Maternal Screening, Part 1


Mayo Medical Laboratories only accepts Nuchal Translucency (NT) measurements from certified sonographers. Mayo Medical Laboratories must review the NT/CRL data for each certified sonographer before a specimen is submitted.

The sonographer must provide the required information by completing the following steps:

  1. Fax a copy of the sonographer's certification card or certificate to 507-538-7709.
  2. Complete and submit the NT/CRL Data Form. Sonographers should provide paired NT/CRL measurements from as many pregnancies as possible to validate the appropriate reference data. If the sonographer does not provide the data, Mayo Medical Laboratories accepts the test requests with appropriate sonographer certification. However, a population-specific reference curve is assigned until sufficient data is received. The relative risk associated with the NT measurement is calculated by comparing the patient's NT measurement to a reference curve.

    Note: If a sonographer's technique differs significantly from that of the reference curve, the accuracy of the results will be compromised.

After the NT/CRL data review is complete, Mayo Medical Laboratories provides a sonographer code to the sonographer. The sonographer code must be included with each specimen submitted.

Clinic personnel must complete the First Trimester/Sequential Maternal Screening Patient Information form (T593) for each patient and include the form with each specimen submitted.

Mayo Medical Laboratories sends a quality report to each sonographer within a minimum of 50 data points. The report includes the number of measurements, median, slope, and standard deviation. Sonographers falling outside expected norms are asked to contact their certification agency for remediation. Sonographers who continue to fall outside of expected norms might be required to submit a letter from their certification agency validating their ability to continue to perform nuchal translucency measurements.

If you have questions, contact Customer Service and ask for the maternal screening area: 800-533-1710