What is PGT-M?

PGT-M — preimplantation genetic testing for monogenic disorders — tests embryos created through IVF for a specific inherited condition that is already known in your family, so that unaffected embryos can be selected for transfer. The key word is specific. PGT-M is built around one known gene change. It is not a general screen. The process has two stages, and the first surprises many couples: A preclinical work-up comes before your IVF cycle. The laboratory identifies your exact gene change, then designs and validates a test around it — often using DNA samples from you, your partner, and sometimes other family members. This takes time and must be completed before treatment starts. Then the clinical cycle: IVF, embryo biopsy, testing, and transfer of an unaffected embryo. What your work-up report should contain, per ESHRE: the gene and the specific variant named properly, the testing strategy, the test's limitations, and the residual risk of misdiagnosis for your particular set-up — with a graphic presentation of that risk. Results are reported per embryo as unaffected, carrier or affected. ESHRE specifies that results must not be communicated orally — you should receive a written report, and it should be discussed with you before embryo transfer. Embryos with no result or an inconclusive result are not recommended for transfer.