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α-Fetoprotein (AFP) Tetra Profile

CPT: [MAAA: 81511] or 82105; 82677; 84702; 86336
[MAAA: 81511] or 82105; 82677; 84702; 86336[MAAA: 81511] or 82105; 82677; 84702; 86336
[MAAA: 81511] or 82105; 82677; 84702; 86336[MAAA: 81511] or 82105; 82677; 84702; 86336
Updated on 12/9/2019
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  • AFP Tetra
  • Alpha-Fetoprotein (AFP) Tetra Profile

Test Includes

α-Fetoprotein, serum; dimeric inhibin A (DIA); human chorionic gonadotropin (hCG); unconjugated estriol (uE3)

Special Instructions

The following information must be provided: gestational age, date on which the patient was the stated gestational age, how gestational age was determined (LMP, EDD, US), patient's weight, patient's date of birth, patient's race (white, black, other), and insulin-dependent diabetic status. Also indicate relevant patient history (eg, prior neural tube defects, Down syndrome, ultrasound anomalies, or previous maternal serum screening specimen during this pregnancy). Complete information is necessary to interpret the test. Patient information may be provided to the laboratory using The Maternal Prenatal Screening requisition form 0900. Specimens must be collected before amniocentesis.

Down syndrome screening is offered for gestational ages 15.0 to 21.9 weeks. Open spina bifida screening is offered for gestational ages 15.0 to 23.9 weeks. The optimal gestational age for open spina bifida screening is 16.0 to 18.9 weeks.

Expected Turnaround Time

2 - 5 days

Related Documents

For more information, please view the literature below.

AFP Tetra Facts (Información sobre AFP Tetra)

Specimen Requirements




5 mL

Minimum Volume

3 mL (Note: This volume does not allow for repeat testing.)


Gel-barrier tube


Collect in serum separator tube with gel barrier. Allow blood to clot, avoiding hemolysis. Separate serum from cells by centrifugation. Transport spun tube to testing laboratory.

Pour-off is not advised. Maternal serum specimens must be drawn prior to amniocentesis to avoid contamination with fetal blood.

Storage Instructions

Room temperature

Stability Requirements



Room temperature

7 days


14 days


14 days

Freeze/thaw cycles

Stable x3

Causes for Rejection

Gross hemolysis; gross lipemia; quantity not sufficient for analysis; improper specimen type

Test Details


Screening test for open neural tube defects (detects 80% open spina bifida, 90% anencephaly), Down syndrome (detects 75% to 80%), and trisomy 18 (detects 73%)


AFP tetra is a screening test. A positive AFP tetra result means that more diagnostic testing may be offered to the pregnant woman to determine if a neural tube defect or chromosome abnormality is present.


Chemiluminescent immunoassay


Haddow JE, Palomaki GE, Knight GJ, Foster DL, Neveux LM. Second trimester screening for Down's syndrome using maternal serum dimeric inhibin A. J Med Screen. 1998; 5(3):115-119. 9795869


Order Code Order Code Name Order Loinc Result Code Result Code Name UofM Result LOINC
017319 AFP Tetra 017389 Results N/A
017319 AFP Tetra 017320 Test Results: 49092-0
017319 AFP Tetra 017368 Gest. Age on Collection Date WEEKS 18185-9
017319 AFP Tetra 017369 Gestat. Age Based On 21299-3
017319 AFP Tetra 017370 Maternal Age At EDD yr 43993-5
017319 AFP Tetra 017371 Race 21484-1
017319 AFP Tetra 017372 Weight lbs 29463-7
017319 AFP Tetra 017373 Insulin Dep Diabetes 44877-9
017319 AFP Tetra 017374 Multiple Gestation 45371-2
017319 AFP Tetra 017375 AFP Value ng/mL 1834-1
017319 AFP Tetra 017376 AFP MoM 23811-3
017319 AFP Tetra 017377 hCG Value mIU/mL 19080-1
017319 AFP Tetra 017378 hCG MoM 32166-1
017319 AFP Tetra 017379 uE3 Value ng/mL 2250-9
017319 AFP Tetra 017380 uE3 MoM 21264-7
017319 AFP Tetra 017381 DIA Value pg/mL 23883-2
017319 AFP Tetra 017382 DIA MoM 36904-1
017319 AFP Tetra 017383 OSBR Risk 1 IN 48803-1
017319 AFP Tetra 017384 DSR (Second Trimester) 1 IN 43995-0
017319 AFP Tetra 017385 DSR (By Age) 1 IN 49090-4
017319 AFP Tetra 017392 T18 Risk 43994-3
017319 AFP Tetra 017391 T18 (By Age) 47223-3
017319 AFP Tetra 017388 Interpretation 49092-0
017319 AFP Tetra 018014 Comments: N/A
017319 AFP Tetra 511933 PDF 11502-2

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