So as it goes, why is it so necessary for the couple to pass genetic testing?
Firstly, to find out the reasons why pregnancy does not happen after 12 months of regular unprotected sex.
Secondly, in order not to transmit a genetic disease to an offspring.
Thirdly, to optimize the chances when using assisted reproductive technology (ART).
Nowadays, the diagnostic of infertile couples includes biochemical and instrumental analyses (which is enough in 65% of cases). In the remaining 35% – genetic testing is added.
A fertility expert may also advise evaluating embryos prior to transfer by means of preimplantation genetic testing (PGT). This complex laboratory procedure allows examining of some of the embryo’s cells at its developmental stage.
For the first time, ICSI Clinic performed PGT in 2003 due to the risk of X-linked disease (Haemophilia A).
Now let’s have a more precise look at types of genetic testing.
- PGT – A is a test for chromosomal aneuploidy – the gain or loss of one or more chromosomes from the normal number. A fertility expert will offer it in the cases of recurrent miscarriage, advanced maternity age, recurrent implantation failure, and severe male infertility.
- PGT – M is aimed to diagnose monogenic genetic disorders (mutations in a single gene, rather than by different genetic factors).
- PGT – SR – is the testing for structural chromosomal rearrangement (translocation, inversion, insertion).
Finally, how genetic testing is done?
- Lab specialists remove some cells of the embryo on days 5-6 of development.
- Removed cells are evaluated for certain genetic properties.
- After a biopsy, the embryos are frozen until results are reported.
- Using PGT results, a fertility doctor determines which embryos would be optimal for the transfer.
IMPORTANT!
There are NO risks to the embryos!
Embryologists take a few cells of trophectoderm. The latter is destined to become the placenta and NOT the part of the embryo!