Prenatal chromosome analysis | Classical cytogenetics
| Test Details | Detects aneuploidy, rearrangements, deletions, inversions |
| Methodology | Chromosome analysis / karyotype |
| Performed | Monday – Saturday |
| Turnaround | 14 days |
| Specimen Requirements | Amniotic fluid (AF), chorionic villi sampling (CVS), percutaneous umbilical blood sampling (PUBS) |
| Sample Collection | AF: Discard first 2mL of amniotic fluid. Collect 15-25mL in a sterile syringe. Use sterile technique to transfer to 15mL sterile screw-top plastic conical tubes for transport. Do not centrifuge. CVS: Collect 15-40mg of budding villi in 50mL screw-top plastic conical tubes in sterile transport media (provided by cytogenetics lab). Do not centrifuge. PUBS: Collect 1-3mL in sterile, 15mL sodium heparin (green-top) Vacutainer tube. Collect under ultrasound guidance. Invert tube immediately upon completion of blood collection to prevent formation of clots. |
| Storage/Transport Conditions | Room temperature |
| Unacceptable Conditions | Will not be accepted after three days |
| Special Instructions | Refrigerate if sample cannot be delivered within 24 hours; Send to Rapid Response or SLCH Central Receiving: Uniquely identify twins/multiples |
| CPT Code(s) | 88291×1, 88235×1, 88269×1, 88280×1 |