Genetics
in Fertility

The genetic makeup of both partners matters. A person may be a carrier of a genetic alteration without experiencing any symptoms, yet this can increase the risk of:
•    Embryos with chromosomal abnormalities
•    Implantation failure
•    Miscarriage
•    Pregnancy loss

What Is Couple Karyotyping?

Couple karyotyping is a genetic test performed using a simple blood sample collected from both partners.
This analysis evaluates:
•    The number and structure of chromosomes
•    The presence of balanced chromosomal rearrangements (such as inversions), which may exist without causing symptoms

A karyotype does not determine whether a couple can have children. However, it provides important information about genetic risk and helps the physician establish the most appropriate treatment strategy.

1. Cell biopsy is performed at the blastocyst stage of embryo development.
2. A very small number of cells are removed (approximately 5 to 7 out of 100 to 150 cells).
3. The sampled cells come from the trophectoderm, the structure that later contributes to placenta formation. The inner cell mass, which develops into the baby, is not affected.
4. The procedure is performed with great precision by experienced embryologists according to international protocols.
5. When performed according to current protocols by experienced professionals, blastocyst biopsy is considered a procedure with minimal impact on embryo developmental potential.

Embryo Selection Following Genetic Testing

• Embryos are vitrified (cryopreserved) under highly secure conditions.
• Samples are sent to the genetics laboratory.
• Based on the results, the embryo with the highest potential to achieve a successful pregnancy is selected.

Preimplantation genetic testing provides valuable information about the embryo's genetic profile; however, pregnancy success also depends on other factors.

Preparing the Uterus for Embryo Transfer

After selecting the embryo with the best genetic potential, the next step is evaluating the environment where the embryo will be transferred.
A genetically healthy embryo requires a receptive endometrium and a favorable uterine environment to implant and develop normally.

A genetically normal embryo does not guarantee pregnancy if uterine, hormonal, or immunological factors prevent implantation.

Before embryo transfer, uterine receptivity is assessed and, when necessary, additional investigations are performed to confirm that the endometrium is prepared to support implantation and pregnancy development.

These may include:

1. Endometrial Receptivity Analysis (ERA). ERA may provide additional information regarding the timing of embryo transfer in selected clinical situations.
2. Endometrial Microbiome Analysis (EMA). It analyzes the composition of the endometrial microbiome and may identify microorganisms associated with an altered uterine environment.
3. KIR + HLA-C Testing (Immunological Compatibility Assessment). It provides information about certain maternal-embryo immunogenetic interactions, the clinical relevance of which should be assessed in the context of each individual case.

Embryo Transfer

IVF success is influenced by multiple factors, among which embryo quality and uterine receptivity are particularly important.

When both conditions are met, the likelihood of achieving an ongoing pregnancy may be more favorable.

Once a favorable uterine environment has been confirmed, the optimal timing for transferring the selected embryo is established.