||Quantitative Chemiluminescent Immunoassay
#ExistPATIENTPREP>Patient Prep: This test requires a nuchal translucency (NT) measurement that has been performed by a certified ultrasonographer. The ultrasonographer MUST be certified to perform NT measurements by one of the following agencies: Fetal Medicine Foundation (FMF) or Nuchal Translucency Quality Review (NTQR). To avoid possible test delays for an ultrasonographer that is new to our database, please contact the genetic counselor at 800-242-2787 extension 2141 prior to sending specimen.
If an NT is unobtainable, order Maternal Serum Screening, Integrated (ARUP test codes 0081062 and 0081064), which can be interpreted without an NT value.
Specimen must be drawn between 11 weeks, 0 days and 13 weeks, 6 days gestation (Crown-Rump length (CRL) must be 4.2-8.5 cm).
#ExistCollect>Collect: Serum separator tube or plain red.
#ExistSPECIMENPREPARATION>Specimen Preparation: Separate serum from cells ASAP or within 2 hours of collection. Transfer 3 mL serum to an ARUP Standard Transport Tube. (Min: 1 mL)
#ExistSPECTRANSPORT>Storage/Transport Temperature: Refrigerated.
#ExistRemarks>Remarks: The sequential maternal screen also requires the following information: a crown-rump length measurement (cm), ultrasonographer's name and certification number, date of ultrasound, patient's date of birth, current weight, due date, number of fetuses present, patient's race, if the patient requires insulin, if there is a known family history of neural tube defects, if the patient has had a previous pregnancy with a chromosome abnormality, if the patient is taking valproic acid or carbamazepine (Tegretol®), physician's name and phone number, and for in vitro fertilization pregnancies, the age of the egg donor.
#ExistConditions>Unacceptable Conditions: A crown rump length greater than 8.5 cm. Plasma. Specimens exposed to repeated freeze/thaw cycles. Hemolyzed specimens.
#ExistStability>Stability (collection to initiation of testing): After separation from cells: Ambient: 8 hours; Refrigerated: 2 weeks; Frozen: 2 months