Clinical Indication
- Spontaneous IUFD/Stillbirth with or without Congenital anomalies
- A Maternal sample (buccal or blood) is required with all fetal POC samples (excluding pathology specimens) to rule out maternal DNA contamination, which can interfere with the interpretation of results.
- Paternal samples are not required.
Testing options:
Targeted Aneuploidy by QFPCR for common aneuploidies
- Detects the following targeted fetal aneuploidies commonly associated with pregnancy loss:
- Trisomy 21
- Trisomy 13
- Trisomy 18
- Sex chromosome aneuploidies (including Monosomy X)
- Triploidy
Microarray analysis after a non-diagnostic QFPCR result for appropriate clinical indications:
- Fetal congenital anomalies (refer to Table 1)
- Recurrent pregnancy loss (≥ 3 losses)
- Not clinically indicated when an IUFD/stillbirth has an existing clinical explanation:
- Previable ruptured membranes
- Preterm cervical change
- Placental abruption
- Intrauterine infection
- Evidence of cord accident
- Maternal condition associated with IUFD (eg. Severe preeclampsia)
- Targeted Aneuploidy QFPCR testing will always precede microarray testing
- Can only be done if quality and quantity of DNA extracted from the sample is sufficient
- In the setting of fetal anomalies, consultation with Medical Genetics is recommended prior to requesting microarray testing, as additional genetic testing may be indicated (see below)
- Consultation with Medical Genetics is required for consideration of microarray or other genetic testing if no anomalies have been identified in the fetus, and there is no history of recurrent pregnancy loss
Other Genetic Testing for a fetus with identified anomalies after a non-diagnostic microarray result:
- up to 10-12% of cases may be explained by pathogenic variants in single genes that are not detected by microarray
- Medical Genetics consult is required for consideration of additional genetic testing
- Maritime Medical Genetics Service can be contacted at (902) 470-8754
Table 1. IWK Clinical Genomics Laboratory: Criteria for Fetal Microarray Testing for IUFD and Stillbirth
| Indicated | Not Indicated |
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