Preimplantation genetic screening (PGS)

Genetic diagnostics of embryos before transfer to the uterus increases:

• chances of successful IVF;
• the probability of having a genetically healthy child.

Reduces:

• risk of complications during pregnancy;
• the need for repeated IVF cycles (which reduces the time and cost of treatment).

Preimplantation genetic screening allows us to exclude the possibility of developing monogenic chromosomal diseases in the embryo: cystic fibrosis, spinal muscular atrophy, neurofibromatosis, Marfan syndrome, Huntington’s chorea, Martin-Bell syndrome, Duchenne muscular dystrophy, as well as chromosomal abnormalities: Down syndrome, Edwards syndrome. syndrome, Patau syndrome.

PGS is performed in the following cases:

• infertility of unclear genesis in couples of young reproductive age;
• the woman’s age is 35 years and older and she is not pregnant when receiving embryos with normal morphology;
• the expectant mother’s age is 37 years and older;
• 2 or more unsuccessful IVF cycles in the couple’s history;
• Reduced sperm counts (e.g., oligoasthenoteratozoospermia, azoospermia, high sperm DNA fragmentation, poor sperm morphology).

Preimplantation genetic screening is recommended in case of altered karyotype of the parents and a high risk of hereditary pathology transmission to the child:

• one/both parents are carriers of balanced chromosomal aberrations;
• male infertility associated with microdeletion of the AZF locus;
• one/both parents are carriers of X-linked mutations.

The following methods of preimplantation genetic screening are used in theIVMEDclinic:

• NGS;
• PCR;
• FISH;
• CGN.

Features of PGS:

• 100% – all chromosomes of the embryo are studied during the test;
• 5 – diagnostics is performed on the 5th day of embryo development, when only blastocysts with a high potential for implantation can be selected for examination;
• 70% – increasing the probability of successful IVF to 70% in patients of young reproductive age;
• 7% – thanks to PGS, the risk of spontaneous early termination of pregnancy is reduced to 6.9%;
• 99% accuracy of preimplantation genetic screening results;
• 0.07% – up to 0.07% of embryo cells are required for PGS, and the biopsy does not affect the cells from which fetal organs are subsequently formed;
• 99% – the percentage of survival of vitrified embryos and their subsequent successful implantation after PGS.

The procedure for preimplantation genetic screening

1. PGS is performed as part of the IVF program on the 5th day of embryo development, when it reaches the blastocyst stage. At this stage, it is possible to obtain more accurate and complete information about the genetic health of the embryo.
2. With the help of micro instruments, the embryologist takes up to 10 cells of the upper layer of the embryo (trophectoderm) for analysis. This procedure is called an embryo biopsy. The internal cell mass, which will later form the organs of the embryo, is not touched during the biopsy.
3. After taking the cells for the study, the embryos are vitrified for the period required for preimplantation genetic screening using the selected method (NGS, PCR, FISH, CGN). Vitrification is a safe method of rapid freezing of blastocysts, which prevents their damage and does not interfere with the subsequent successful implantation of embryos in the uterus.
4. Based on the data obtained as a result of preimplantation genetic screening, the embryologists of theIVMEDclinic select euploid (genetically normal) embryos. One of them is thawed and, after preliminary medical preparation, the woman transfers it into the uterus for further implantation and pregnancy. The remaining euploid embryos can be stored in our cryobank and, if necessary, used in subsequent IVF cycles.
5. Based on the results of PGS, a couple can also decide to repeat the IVF cycle with their own eggs/sperm or use a program with donor cells (in case of unsatisfactory PGS results with their own reproductive cells).

To increase the chances of a successful pregnancy and the birth of a genetically healthy child, use preimplantation genetic screening PGS at theIVMEDclinic.