Chromosome Analysis, Amniotic Fluid
Also known as: Karyotype, Amniotic Fluid
Use
The test determines fetal karyotype. The test allows prenatal detection of chromosomal rearrangements, aneuploidy, or mosaicism. Such groups include women who:
Special Instructions
If prior Non-Invasive Prenatal Testing (NIPT) studies have been performed, include a copy of the report with the specimen. Specimens from twin pregnancies should be labeled separately and accompanied by distinct request forms. Maintain the specimen at room temperature and avoid freezing. Discard the first 2 mL of fluid to prevent maternal cell contamination.
Limitations
Despite a high reported culture success rate of over 99%, potential culture failures can occur due to lack of amniocytes in the fluid or contamination with bacteria or yeast. While this test provides substantial genetic insights, it does not rule out all congenital anomalies nor subtler rearrangements below the resolution capacity of cytogenetic analysis. The method has been developed by Labcorp, yet it is not FDA cleared or approved.
Methodology
Cell-based / Cytometry (Karyotype)
Biomarkers
LOINC Codes
- 62386-8
- 64095-3
- 64096-1
- 64092-0
- 64091-2
- 64093-8
- 62356-1
- 62357-9
- 48002-0
- 48672-0
- 11502-2
Result Turnaround Time
9-12 days
Related Documents
For more information, please review the documents below
Specimen
Amniotic Fluid
Volume
15-20 mL (20-30 mL for early amniocentesis)
Minimum Volume
5 mL
Container
Sterile plastic conical tube
Collection Instructions
Discard first 2 mL of fluid to avoid maternal cell contamination. Collect in a 20 mL sterile syringe and transfer aseptically to sterile tubes.
Patient Preparation
Preferably, the patient should have ultrasound studies to verify fetal life, detect multiple gestation, confirm gestational age, and localize fetus/placenta.
Storage Instructions
Maintain specimen at room temperature. Do not freeze.
Causes for Rejection
Suitability determined by Cytogenetics laboratory upon receipt.