BillionToOne Replaces Two-Step Carrier Screening

BillionToOne is winning by replacing a two step prenatal workflow with a one draw test that pays like the old workflow but does more. In traditional carrier screening, the mother is screened first, then if she is a carrier the partner often needs separate testing and genetic counseling. UNITY uses one maternal blood sample to estimate fetal risk directly, which removes a major drop off point for OB practices while still fitting existing carrier screening reimbursement pathways.

• The practical advantage is workflow, not just better science. An OB can collect one tube of maternal blood, send it to a single lab, and get fetal risk for recessive conditions without waiting for the father to show up, agree to testing, or produce a usable sample. That makes adoption easier inside busy prenatal clinics.
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• Traditional carrier screens like Myriad Foresight still frame a positive maternal result around partner testing and counseling as next steps. BillionToOne moved that decision tree into the lab by reading fetal DNA from maternal blood, so it can take share from carrier screening budgets instead of needing a new reimbursement bucket.
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• This matters because prenatal diagnostics is a scale business. BillionToOne reached about 15% U.S. prenatal share and $153M of revenue in 2024, with average prenatal selling prices approaching $400 and costs trending toward $100, showing that a simpler clinic workflow can convert into real volume without giving up unit economics.
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The next step is broadening the same one draw prenatal wedge into a fuller standard of care. The expanded UNITY Fetal Risk Screen now covers up to 14 recessive and X-linked conditions from a single maternal sample, which gives BillionToOne more chances to displace older carrier screening panels and deepen its hold in OB practices before rivals fully match the workflow.