Microarray, Prenatal

Diagnostic Use

A chromosomal microarray (CMA) is used to detect small genomic changes. The CMA provides a genome-wide analysis of DNA copy number changes, with targeted probe coverage in disease-associated regions. It detects microduplications and microdeletions around 100 times smaller than those seen by conventional G-band chromosome analysis (karyotype). The inclusion of single nucleotide polymorphism (SNP) probes in the microarray design enables the detection of large regions of homozygosity, which can indicate uniparental disomy or recessive disease.
This test does not detect sequence-based changes, fragile X, low level mosaicism, or balanced chromosome rearrangements.

Indications for testing:
1. One or more structural fetal anomalies detected by ultrasound (including IUGR or NT >3.5mm)
2. Structural chromosome imbalance identified by G-band karyotyping
3. Family history of a chromosome rearrangement. Liaison with Genetic Health NZ or this laboratory is recommended to determine the most appropriate investigation
4. On a case by case basis following consultation with a Clinical Geneticist, a Pathologist or Fetal-Maternal Medicine specialist


Genetics - Cytogenetics

Delphic Registration Code



Fetal microarray
Molecular karyotype, prenatal
Prenatal microarray

Turnaround Time

15 days

Test Code