An observational study in Pregnant Individuals, Aneuploidy and Down Syndrome (Trisomy 21), sponsored by BillionToOne Inc.. Recruiting at 9 sites in United States. Open to female participants. Per ClinicalTrials.gov, last updated 2026-10-15.
Sponsored by BillionToOne Inc. · Observational
The goal of the ADVANCE (Assay Development and Validation for Pre-Natal and Obstetric Conditions) study is to compare the concordance of results of a novel non-invasive circulating fetal cell (CFC) assay to the results of prenatal invasive diagnostic testing or postnatal genetic and clinical diagnosis of the resulting neonate. This is a prospective study of pregnant individuals.
BillionToOne Inc. is conducting a large prospective study to evaluate the performance of a non-invasive circulating fetal cell (CFC) assay. Circulating fetal cells, rare, intact trophoblast cells of placental origin present in maternal blood, offer a unique opportunity to directly analyze fetal genetic material without the need for invasive procedures. These cells are most abundant during the first trimester of pregnancy.
Building on this biology, the investigators developed a circulating fetal cell assay (UNITY Confirm) that isolates fetal-derived placenta cells from maternal blood and performs single-cell genomic analysis to assess chromosomal copy number. By combining cell-type-specific markers and genotyping to distinguish fetal from maternal cells, this approach enables direct evaluation of fetal chromosomal status, unlike cfDNA methods that rely on analysis of mixed DNA fragments.
This prospective study enrolls pregnant individuals between 10 and 20 weeks of gestation with singleton pregnancies and aims to include over 1,000 participants. CFC testing results are compared to prenatal or postnatal diagnostic outcomes.
73 studies on the registry are indexed under Aneuploidy; 10 are open to participants now.
This study's planned enrollment of 1,000 is above the median of 325 across 38 observational studies indexed under Aneuploidy.
Browse Aneuploidy studies →This is the only study on the registry with BillionToOne Inc. as lead sponsor.
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pregnant individuals between 10 and 20 weeks of gestation with singleton pregnancies
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Exclusion Criteria:
- active cancer
Pregnant individuals between 10 and 20 weeks of gestation with singleton pregnancies and who have a clinical indication for CFC testing, such as high-risk cfDNA results for common aneuploidies, copy number variants including 22q11.2, or sex chromosome aneuploidies
Pregnant individuals between 10 and 20 weeks of gestation with singleton pregnancies (excluding gestational surrogates) who do not have a clinical indication for CFC and are undergoing prenatal diagnostic testing
Concordance
CFC results will be compared with prenatal diagnostic testing results, CVS, amniocentesis, products of conception, when available, and postnatal diagnostic testing.
Time frame: From enrollment and up to 12 months following enrollment
Concordance with the accepted method of diagnosis
CFC results will be compared with prenatal diagnostic testing results, CVS, amniocentesis, products of conception, when available, and postnatal diagnostic testing. Results are considered concordant when CFC findings are consistent with the known or fetal or neonatal diagnosis.
Time frame: From enrollment and up to 12 months following enrollment
Plan to share: Yes — CFC result and diagnostic testing result
Supporting information: Informed consent form, Clinical study report
Time frame: when data collection is complete and up to 2 years post-study completion date
Access criteria: Other researchers after the appropriate date use agreements are in place.
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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