AFP, Maternal Serum; Alpha-Fetoprotein (AFP), Maternal Serum for Open Spina Bifida; Maternal Serum α-Fetoprotein; msAFP;
Expected Turnaround Time
2 - 5 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Whole blood or serum (unhemolyzed)
Serum: 2-3 mL
Whole Blood: 7 mL
Serum: AFP tube
Whole Blood: Serum separator tube (SST) or red-top tube
Whole Blood: allow to clot; centrifuge (15 minutes at 1,500 rpm) to prevent hemolysis.
Causes for Rejection
Gross hemolysis; gross lipemia; quantity not sufficient for analysis
Risk assessment for fetal open neural tube defects.
At 15w-23w6d (optimal 16w-18w6d)
Immunochemiluminometric assay (ICMA)