PGT-A

Preimplantation genetic testing for aneuploidy, or PGT-A, is a laboratory test used alongside IVF. Embryos are grown until they reach the blastocyst stage, a few cells are sampled from the outer layer, and the sample is analysed for missing or extra chromosomes.

The result describes the tested sample, not every cell in the embryo. PGT-A does not test for every genetic condition, and it does not replace pregnancy screening or diagnostic testing.

IVF creates embryos in the laboratory. After blastocyst culture, an embryologist takes a small biopsy, freezes the embryo and sends the sample for analysis. The fertility team discusses the report, selects an embryo when appropriate and plans a later frozen transfer.

The biopsy is performed on the embryo’s outer cells, while the embryo remains frozen during testing. PGT-A does not guarantee implantation, a healthy pregnancy or a baby without genetic conditions. Your clinic discusses biopsy, freezing, transfer and pregnancy-testing considerations before consent.

You can discuss IVF without PGT-A, PGT-A with transfer decisions guided by the report, or other genetic testing when a known inherited condition is the concern. Ask how your clinic handles mosaic or inconclusive results, embryos that are not suitable for transfer and the option of genetic counselling.

PGT-A focuses on chromosome number rather than a complete health assessment. Some embryos may have mixed results or no result, and not every embryo reaches the stage where biopsy is possible. A result must be interpreted with age, fertility history and the rest of the IVF plan.

People considering IVF may ask about PGT-A when chromosome-number differences are a particular concern, or after discussions about embryo selection and previous treatment experiences. Suitability depends on the number and quality of embryos available, medical history, goals and local clinic practice; it is not automatically useful for everyone.

The clinic assesses your fertility history and explains consent. IVF stimulation and egg collection are followed by fertilisation and embryo culture. Suitable blastocysts are biopsied and frozen, the sample is tested, and the team reviews the report with you before deciding whether and when to transfer an embryo.

There is no physical recovery from the embryo biopsy for you; recovery relates to egg collection and any hormonal treatment used for IVF. You may wait for the laboratory report while embryos remain frozen. If transfer goes ahead, pregnancy testing and follow-up occur on the clinic’s schedule.

PGT-A can produce an unclear or mixed result, and a biopsy or freezing process may mean an embryo is not available for transfer. Testing can reduce the number of embryos considered suitable without proving which pregnancy outcome will occur. IVF medicines and procedures have their own risks, which the clinic should explain.

Alternatives include IVF without embryo chromosome testing, genetic counselling, testing for a known inherited condition when relevant, and routine pregnancy screening or diagnostic testing after conception. The best route depends on why testing is being considered and how many embryos are available.

Ask whether the clinic offers counselling before testing, explains mosaic and inconclusive results, and provides a clear plan for embryos with each report. Discuss laboratory quality, consent, storage, transfer timing and what pregnancy testing will still be offered.