Published by INCITA Clinic
On this page
What PGT means
Preimplantation genetic testing is testing carried out using embryo samples before transfer as part of IVF treatment. PGS and PGD are older terms for these forms of testing.
PGT-A
PGT-A examines chromosome number. Aneuploidy means an extra or missing chromosome. This type of testing may be discussed in relation to age and previous implantation failure.
PGT-M
PGT-M is directed at a known single-gene condition. A relevant family history and genetic reports are central to planning.
PGT-SR
PGT-SR addresses structural chromosome rearrangements, such as translocations. The parental chromosome report guides the discussion.
Discuss your results
The test needs to match the clinical question. The doctor and laboratory team can explain which approach is relevant and how results are used in planning treatment.
Different questions, different tests
| Clinical question | Test discussed |
|---|---|
| Chromosome number | PGT-A |
| A known inherited single-gene condition | PGT-M |
| A parental structural chromosome rearrangement | PGT-SR |
The embryo biopsy stage
Testing is part of a planned IVF pathway. Embryos are cultured to the blastocyst stage and outer-layer cells are sampled for analysis. Genetic findings are reviewed before deciding on the transfer plan.
Fertilization method, embryo culture and genetic testing are separate stages. ICSI describes how fertilization is carried out; it does not by itself provide a chromosome or single-gene test.
Why parental reports matter
Normal parental chromosome tests do not mean every embryo will have a normal chromosome number. Equally, a family history of a single-gene condition cannot be answered by a chromosome count alone.
Bring the actual chromosome and genetic reports to the consultation. This allows the doctor and laboratory to identify which genetic question needs to be addressed.
Reports that help identify the question
Scroll across to view all columns.
| Clinical information | Discussion it may inform |
|---|---|
| Age, reproductive history and earlier embryo findings | Whether chromosome-number testing with PGT-A is relevant. |
| A known single-gene condition or identified family variant | The targeted PGT-M question and supporting reports. |
| A parental chromosome rearrangement | PGT-SR planning and the meaning of carrier or non-carrier findings. |
Keep testing and transfer decisions distinct
The number of embryos biopsied, the genetic categories reported and the number considered for transfer are separate observations. An embryo grade is also different from its genetic laboratory result.
Ask what the proposed analysis can report, how the team will discuss the results and which clinical decisions will follow. For related explanations, see age and chromosome findings, laboratory results and single embryo transfer.