GeneDx and Sema4 are now a combined company  Learn more

Zygosity Testing

New York


  • Chromosomal Abnormalities

Clinical Utility

  • Multiple pregnancies

Lab Method

  • PCR & Electrophoresis

Test Code


CPT Codes*


ABN Required


Turnaround Time**

1 week

Preferred Specimen

10 mL Amniotic Fluid

Alternative Specimen

20 mg CVS | 2 T25 flasks of cultured amniocytes | 2 T25 flasks of cultured chorionic villi | 3 Ug DNA Concentration

*The CPT codes provided are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.

**Reporting times are typical and begin once the sample(s) are received at the GeneDx laboratory, but could be extended in situations outside GeneDx’s reasonable control.