Fetal Microarray
- Microarray testing looks broadly at an individual’s genetic information for areas of copy number variation (deletions/duplications) down the size of single or partial genes.
- Fetal microarray is available only for eligible indications (see table below)
- For microarray testing on fetal specimens, a referral to Medical Genetics is:
- Required for all on-going pregnancies.
- Recommended for IUFD/fetal tissue testing when anomalies have been identified, as testing beyond microarray may be indicated.
- Required for IUFD/fetal tissue testing if no anomalies have been identified in the fetus, prior to consideration of microarray testing.
| Indicated | Not Indicated |
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Single fetal anomalies with additional ultrasound findings (eg: fetal growth restriction or overgrowth, oligo- or polyhydramnios, single umbilical artery) |
Soft markers only (includes absent nasal bone, renal pyelectasis, echogenic intracardiac focus, echogenic bowel, brachycephaly, choroid plexus cysts, single umbilical artery) |
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Parents with ≥3 recurrent pregnancy losses |
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| For isolated fetal anomalies without additional ultrasound findings | |
| Indicated | Not Indicated |
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Cardiac – Complex congenital heart anomaly (including hypoplastic left heart, situs inversus, Tetralogy of Fallot, TGA and DORV) |
Cardiac – Non-complex congenital heart anomalies (including atrial septal defect, ventricular septal defect, atrioventricular canal defect and coarctation of the aorta) |
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Craniofacial – Cleft lift and/or palate, abnormal profile, craniosynostosis and microcephaly |
Craniofacial: macrocephaly and brachycephaly |
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Gastrointestinal: congenital diaphragmatic hernia, omphalocele |
Gastrointestinal: duodenal atresia, gastroschisis, tracheoesophageal fistula |
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Genitourinary: ambiguous genitalia, hypospadias, polycystic kidneys, ureteral anomaly Could consider based on presentation at Genetics discretion |
Genitourinary: lower urinary tract obstruction, megacystis, renal agenesis
Could consider based on presentation at Genetics discretion |
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Intracranial: Ventriculomegaly (>15mm)*, absent CSP, cerebellar anomaly, abnormal cisterna magna and agenesis of the corpus callosum |
Intracranial: Isolated choroid plexus cyst |
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Musculoskeletal/cranial: Neural Tube Defect (required for surgery), contractures, limb digit anomalies, polydactyly, talipes and thoracic anomaly |
Musculoskeletal/cranial: Neural Tube Defect (no fetal surgery), acrania/anencephaly and scoliosis |
- *For Ventriculomegaly: Mild (<13mm): generally, don’t offer. Moderate (13-15mm): possibly offer. Severe (>15mm): offer. Also consider L1CAM in males with severe ventriculomegaly if 4th ventricle is normal.