Chromosome Analysis - Prenatal

Chromosome Analysis (includes karotype)
May be performed on:

  • Amniotic Fluid
    • 20-30 ml divided among three 10 mL sterile tubes
    • Also send the 'first draw' of 1 - 3 mL in a separate tube. Make sure to send a completed AFP (alpha-fetoprotein) requisition form if AFP and/or ACHE testing is desired. If an aneuploidy FISH screen is ordered as an adjunct to chromosome testing, the minimum volume is 20 mL of non-bloody fluid. Specimens should be protected from light during transport. 
  • Chorionic Villus Specimen
    • Sterile transport media (RPMI) may be obtained from the cytogenetics lab during work hours (859-257-3736). After hours it may be obtained from Lab Central Receiving (859-323-5431). 
    • 20 - 30 mg of tissue is optimal. 10 mg is the minimum acceptable sample. More than 10 mg is required if FISH, DNA, or biochemical testing is ordered in addition to chromosome analysis. The laboratory should be notified 24 hours in advance of all planned CVS procedures. This will insure a technologist will be available to immediately assess specimen adequacy upon delivery to the lab. Specimens should be sent to the lab by a courier service. CVS procedures should be scheduled to insure delivery to the lab before 3:00 PM Monday - Thursday. Specimens received after 3:00 PM Thursday, Friday, or Saturday, or on a day prior to a holiday, will not have results from a direct preparation. 
  • Cord (fetal) Blood
    • 1-2 ml in sodium heparin


Establishing a fibroblast cell line or growth of additional cells for biochemical/DNA testing on amniotic fluid and chorionic villi specimens may be performed by contacting the lab (859-257-3736). 

Prenatal Requisition

No