Why is next-generation sequencing used in PGT-A?

In PGT-A, a small group of cells is removed from the outer layer of an embryo created through IVF. The laboratory amplifies and sequences genetic material from those cells, then compares the amount assigned to each chromosome. This can identify patterns suggesting an extra or missing chromosome in the tested sample.

The result describes the cells sampled, not a guarantee about every cell in the embryo. Embryos can contain a mixture of cell types, and a result may be reported as abnormal, expected, mosaic, or inconclusive according to the laboratory's system. PGT-A does not test for every inherited condition, and it does not replace pregnancy testing or ultrasound assessment.

Ask the fertility team which chromosome findings the laboratory reports and how it handles mosaic or inconclusive results. Discuss whether the test is suitable for your treatment plan, how embryos are selected for transfer, and whether confirmatory testing is advised during pregnancy. A genetics professional can explain what the report can and cannot show.

Contact the fertility clinic when you receive an unexpected, mosaic, or inconclusive report so the team can explain the options without relying on a single label. After embryo transfer, urgent care is needed for severe pain, heavy bleeding, fainting, or breathing difficulty. Those symptoms require clinical assessment and are not interpreted by PGT-A.

Ask how the biopsy was obtained, what chromosome changes were assessed, what an inconclusive result means, and how the finding affects embryo selection. Ask whether prenatal diagnostic testing will still be offered after pregnancy is established.