Preimplantation genetic testing is a highly specialised technique designed to identify chromosomal aberrations (deviations and changes) or monogenic hereditary diseases before an embryo is transferred to the uterus. The main goal of the testing is to select only the embryos in which no abnormality was detected.

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Through the studying of chromosomal embryo construction it was discovered that the presence of aneuploidy (chromosome deviations) is one of the leading causes of infertility. The examination of the embryo chromosomes can increase the success rate of assisted reproduction. 

The indication for preimplantation genetic testing is most commonly due to the following factors:

  • High risk of chromosomal abnormalities, or serious monogenetic hereditary disease
  • Genetic deviations linked to the gender of the embryo
  • Numerous miscarriages
  • Previous early birth or abortion of an embryo with chromosomal abnormality
  • Numerous unsuccessful rounds of IVF
  • Higher age of the female partner

The pre-implantation genetic testing is performed in the early embryo development stage. After the mechanical opening of the zona pellucida, 5-10 cells are abstracted and they are investigated using one of the methods described below. The embryo biopsy is usually carried out on the 5th day after the fertilisation. Only the embryos that are found to be healthy are then chosen for the embryo transfer.

 The indication for all genetic testing is decided by the doctors.

PGT-A with NGS method

NGS - Next Generation Sequencing - is one of the most high-tech genetic testing methods. The testing is done on the cells that are taken from the embryos in the early blastocyst stage - the 5th day of development. It allows the early detection of structural problems, or any other deviations, on all 24 chromosomes. It is also highly sensitive to the detection of genetically abnormal embryos, having close to a zero mistake rate. NGS testing is especially suitable in cases where one of the partners is a carrier of a genetic disease, for couples who have had numerous miscarriages or for the more mature aged female partner. The indication for NGS is always decided by the doctor.

PGT-M with PCR method

PCR - Polymerase Chain Reaction: A diagnostic method aimed at the detection of specific inheritable genetic diseases. It is applicable for all known monogenic genetic mutations. If there is further suspicion from the doctor or any other reason for indication, further NGS examination is possible on the remaining healthy embryos.


MATCH+ – an additional examination of the 430 most frequent genetic mutations (suitable mainly in therapies with egg donation). The examination ensures safe matching and optimal genetical compatibility of the donor and partner, while still respecting the phenotypical and other requests of the couple.

*Every healthy person is a carrier of 2-5 mutations that do not have any impact on the person. However, in the case where two people with the same mutation partner, it may result in a higher risk of conceiving a genetically handicapped child. The MATCH + serves as an additional filter while adding genetic compatibility into the selection pattern. Match + sets a genetically based criteria according to which your donor is carefully chosen.


The cells that provide natural immunity in the uterus also include NK (natural killer) cells and KIR (Killer-cell immunogloobulin-like receptors). Some receptors may show a high degree of intolerance towards human leukocyte antigen type C (HLA-C) or selected subtypes. HLA types of the egg and sperm and of the KIR receptors in the uterus makes it possible to determine the compatibility between the KIR receptors in the uterus and the HLA-C antigen of the embryo. This allows us to determine the immunological tolerance of the uterus (embryo recipient) to the fetus.

In the context of an HLA+ donor program, we look for a donor in such a way that the optimal combination of the HLA-C antigen (sperm and egg) with respect to the KIR receptors of the uterus (patient) is ensured. HLA+ ensures the optimum possible compatibility of the KIR receptors (uterus) and HLA-C antigens (sperm and egg), therefore significantly increases the chance of carrying the transferred embryo.

Both HLA-C and KIR testing is performed by taking a blood samples. The method is particularly suitable for patients with recurrent complications in carrying the fetus to term.



Ranking+ is a complementary method that determines the implantation potential of embryos and helps to prioritize the most suitable ones for transfer. This method is particularly suitable for patients who are likely to have a large number of suitable oocytes. In addition, because this is a non-invasive method of retrieving cells (niPGT) that are spontaneously released into the culture medium, therefore, the biopsy of the embryo is not necessary. Thus, Ranking+, among other benefits, can increase the success rate of pregnancy by 10 – 15%. We were the first to introduce this method in the Czech Republic. Find out more about the Ranking+ in this article.



Prenatal testing is performed based on the mother’s blood collection in the 10th week of pregnancy. This test allows us to discover the common chromosomal abnormalities with a single or twin pregnancy. This method is focused on trisomy detection and is recommended for females with marginal test results from the 1st trimester screening. This method is used almost exclusively with women who underwent assisted reproduction or with women above 35 years of age.


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