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Structural chromosome changes
PGT-SR addresses changes in chromosome structure, including balanced and Robertsonian translocations. These are different from a simple extra or missing whole chromosome.
The purpose of testing
Testing is used to help identify embryos suitable for consideration for transfer in families affected by structural chromosome rearrangements. The assessment begins with the parental chromosome findings.
Review your chromosome report
Share the full chromosome or genetic report with the hospital. The team can discuss the particular rearrangement, the scope of testing and the results that may be reported.
Balanced and Robertsonian translocations
A structural rearrangement changes the organization of chromosome material. A balanced carrier may have no obvious health problem while still having reproductive difficulties related to unbalanced chromosome material in embryos.
The hospital’s PGT-SR information discusses balanced translocations and Robertsonian translocations. The exact parental chromosome finding is the starting point for planning embryo testing.
Balanced-carrier and non-carrier embryos
A key question is whether the proposed test can distinguish a balanced-carrier embryo from an embryo without that rearrangement. Conventional PGT-SR does not always make this distinction.
INCITA offers testing approaches that can distinguish these categories. The laboratory needs to review the family’s chromosome results to explain the applicable method and what it can report in the individual case.
Connecting laboratory results to clinical planning
PGT-SR uses embryo biopsy material within an IVF pathway. Embryo culture, the biopsy procedure and the planned genetic analysis are coordinated before transfer selection.
A consultation should include discussion of the parental report, earlier pregnancy history and any previous embryo test results. This helps define the genetic question before a cycle starts.
Useful information for the team
- The full parental karyotype or chromosome report
- Previous genetic counseling or laboratory reports
- History of pregnancy loss or earlier embryo testing
- Previous IVF, stimulation and embryo development records
Questions about structural chromosome findings
Why can the parental report matter even if the carrier is healthy?
A balanced rearrangement may be present without an obvious health problem in the carrier. The reproductive question concerns how chromosome material may be distributed in embryos. The full parental chromosome report is therefore important to the assessment.
What should I ask about balanced-carrier and non-carrier results?
Ask whether the proposed method can distinguish an embryo carrying the balanced rearrangement from one without it, and what the laboratory can report for your family. INCITA’s testing approaches can make this distinction after review of the relevant chromosome findings.
Is counting chromosomes enough to answer this question?
PGT-A and PGT-SR have different purposes. A discussion of a structural rearrangement starts with the exact chromosome finding rather than a general request for embryo screening.
What should be agreed before a cycle starts?
Review the parental report, earlier pregnancy or embryo-test findings, the intended analysis and how results will inform transfer planning. Request the relevant USD testing quotation after the team has reviewed the genetic question.
