At the practice of Ioannis Raptis, infertility issues are managed in accordance with the guidelines of the “Frankfurt Hormone School” (Frankfurter Hormonschule) and the International Society of Gynecological Endocrinology (ISGE).
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Preimplantation genetic testing is one of the most significant advancements in the field of assisted reproduction. It offers couples the opportunity to make targeted and safe decisions during the IVF process. Through genetic screening of embryos before implantation, the risk of miscarriage and serious hereditary diseases is reduced.
Every couple considering this option should fully understand what preimplantation genetic testing is, when it is applied, and what its real benefits and limitations are.
Preimplantation genetic testing is a specialized diagnostic procedure performed within the context of in vitro fertilization (IVF) before embryo transfer. Its purpose is to analyze the genetic material of embryos in order to detect chromosomal abnormalities or inherited diseases.
This allows for the selection of genetically healthy embryos, which have a higher likelihood of leading to the birth of a healthy child.
Preimplantation genetic testing is not necessary in every IVF cycle. It is mainly recommended in cases where one parent has a serious hereditary condition or when one or both parents are carriers of a genetic mutation.
It is also applied when there is an increased risk of chromosomal abnormalities. This occurs more frequently in cases of advanced maternal age, a history of recurrent miscarriages, or multiple failed implantation attempts.
Preimplantation genetic testing has different forms, depending on the focus of the analysis. The main types include:
Chromosomal screening (PGT-A):
This evaluates the number of chromosomes in the embryo and detects aneuploidies, meaning deviations from the normal chromosomal number, such as monosomies or trisomies.
Testing for monogenic disorders (PGT-M):
Applied when there is a known hereditary condition, allowing the detection of specific gene mutations.
Testing for structural chromosomal rearrangements (PGT-SR):
Used in cases where one or both parents carry structural chromosomal abnormalities that may affect embryo development.
The choice of the appropriate type of testing is always based on the parents’ medical history and after individualized evaluation of each case.
Testing begins after fertilization of the retrieved eggs in the laboratory. The embryos are cultured for a few days until they reach the blastocyst stage, when their structure is more stable. At this stage, a small number of cells are taken from the outer part of the embryo for analysis.
Until the results are available, the embryos are frozen. Embryo transfer is then scheduled based on the findings of the genetic testing.
Preimplantation genetic testing offers significant benefits, particularly in selected groups of patients. These include:
Increased implantation rates, as embryos with a normal genetic profile are selected.
Reduced risk of miscarriage due to chromosomal abnormalities.
Lower likelihood of giving birth to a child with a serious hereditary disease.
Despite its benefits, preimplantation genetic testing may, in rare cases, have an impact on embryo viability. Possible effects include:
Reduced implantation potential due to embryo injury (up to 2%).
Failure of embryo survival after thawing (up to 3%).
Loss of the embryo during the procedure (up to 1%).
False abnormal results leading to the rejection of a viable embryo (up to 10%).
When the method is applied selectively in appropriately chosen patients, these potential risks are generally outweighed by its documented benefits.
There are several common myths that often cause confusion:
Embryos are genetically modified: In reality, this is purely a diagnostic procedure.
It guarantees IVF success: Preimplantation genetic testing cannot guarantee the success of an IVF cycle.
It replaces prenatal testing during pregnancy: It does not replace prenatal screening but rather complements it.
Clarifying these misconceptions helps couples better understand the role and limitations of the method.
The decision to proceed with preimplantation genetic testing should be made after specialized evaluation by the treating physician and, when necessary, by a genetic specialist. Every couple has unique characteristics, a distinct medical history, and different expectations, making an individualized approach essential. When properly applied, preimplantation genetic testing is a highly valuable tool for achieving pregnancy and the birth of a healthy child.
For specialized guidance and support at every stage of IVF treatment, obstetrician–gynecologist Ioannis Raptis and his team are at your disposal. Contact us.
