Anora Miscarriage Test | Clinician Information | Natera


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About Anora

Anora uses chromosomal microarray analysis featuring single nucleotide polymorphism (SNP) technology. Combined with Parental Support™ technology, Anora provides more comprehensive results across all chromosomes than standard karyotyping and array comparative genomic hybridization (CGH).


Conditions screened

Anora is clinically validated to detect whole chromosome aneuploidy, triploidy, tetraploidy, uniparental disomy, and deletions and duplications greater than 5 Mb. Terminal deletions or duplications and clinically significant deletions and duplications down to 1 Mb are also reported.

The Anora difference

  • Approximately one week turnaround time, allowing for faster follow-up care
  • No cell culture needed; less than 1% chance of test failure
  • Higher detection rates than all other products of conception (POC) tests on the market
  • Reports only clinically significant deletions and duplications, with clear follow-up recommendations
  • Able to determine parent of origin for most chromosome abnormalities
  • Detection of maternal cell contamination with a single test
  • Identifies chromosome abnormalities associated with increased risk of gestational trophoblastic disease (GTD) (complete paternal UPD and triploidy of paternal origin)
  • Paraffin POC testing can be performed for previous losses
  • Only a small (pea-sized) amount of tissue required


Faster results, improved accuracy

Anora testing has advantages over standard karyotyping. Only Anora miscarriage testing uses a SNP microarray combined with Parental Support technology to give highly accurate results. Since no cell culture is needed, the chance of test failure is less than 1% and results can be returned within five business days. With Anora testing, a sample of the mother’s blood is requested for comparison to the miscarriage tissue sample. This enables the lab to determine whether a normal female chromosome result is truly fetal or due to maternal cell contamination. Published literature shows that without this maternal testing, over half of "normal female" results are actually results of testing the mother, not the pregnancy that was miscarried. In standard karyotyping, there is no way to differentiate a normal female result as fetal or maternal in origin.

Traditional chromosome analysis, often called a "karyotype," requires growing cells in the laboratory (cell culture). This process takes up to a month and is not always successful. Up to 25% of the time, cell culture fails, leading to no test results.


Distinguish between maternal and fetal DNA

Anora identifies maternal cell contamination (MCC) by using a maternal blood sample or buccal swab to distinguish between fetal and maternal DNA. Properly identifying fetal versus maternal DNA avoids not knowing if a normal female result is fetal or due to MCC.

Identify the origin of molar pregnancy

Molar pregnancies can carry serious risks to the mother, including a type of cancer called gestational trophoblastic disease (GTD). The detection of a molar pregnancy is crucial to your patient’s clinical management. Full paternal UPD and triploidy of paternal origin carry a risk of molar pregnancy for your patient.

Anora is the only miscarriage test that identifies the parental origin of triploidy. This is important because triploidy of maternal origin is not a cause of a molar pregnancy and does not put a woman at risk for GTD.

How can testing help with suspected molar pregnancy?

In Caucasian populations, molar pregnancies occur at a rate of 1/1,000, while in Southeast Asian populations, the rate is 1/125. In the US, there are 6,000 molar pregnancies each year.

Complete molar pregnancies with complete paternal uniparental disomy (UPD) have a 25% risk for GTD. Partial molar pregnancies with triploidy of paternal origin carry up to a 5% risk of disease. If found, GTD can be treated with chemotherapy.

Complete molar pregnancy

Complete molar pregnancy (CMP) typically occurs when an empty egg is fertilized by a sperm that duplicates, or when an empty egg is fertilized by two sperm. This results in complete paternal uniparental disomy (UPD) of all the chromosomes. Complete paternal UPD cannot be distinguished from a normal 46,XX result using other types of POC testing, such as karyotyping or array CGH.

Partial molar pregnancy

Partial molar pregnancy (PMP) occurs when a normal egg is fertilized by two sperm. This results in triploidy of paternal origin (i.e. 69,XXX or 69,XXY; paternal). Triploidy of maternal origin is not a cause of molar pregnancy.