You have been trying to get pregnant for a long time and have opted for artificial insemination (IVF, ICSI). Your desired child should get the best possible start in life and be born without serious health problems, but there is a hereditary genetic or chromosomal disease in your family, or either yourself or your partner is affected.
Through pre-implantation diagnosis we clarify whether your eggs or embryos are healthy. It allows us to select specific unencumbered oocytes or embryos and to avoidgenetic defects in your baby.
The health of a child depends largely on the health of their genes. These genes, their genetic material, are located in the chromosomes. A human basically has 23 + 1 chromosome pairs, wherethe individual genes are stored. For almost all genetically determined human characteristics, the individual genes must be present on both parts of their chromosome pair.
In some people, individual genes are "shifted" (translocation). They are located only on one chromosome of the chromosome pair. As a result, some genes are duplicated on one chromosome, others are not. Simple translocations can be detected by a blood sample (karyogram).
We examine other genetic defects with the methods of preimplantation genetic diagnosis. This clarifies whether genetic diseases or chromosome damage are present, whichare highly likely to prevent healthy cell development. PID can be carried out on oocytes and embryos. Precondition for the pre-implantation diagnosis is that an artificial insemination (IVF, ICSI) takes place. The examination takes place outside the body, even beforewe transfer the embryo into the uterus.
Before we carry out a pre-implantation diagnosis, we will inform you in detail about the methods and the individual steps of the different procedures. We know that the decision on artificial insemination and pre-implantation diagnostics raises questions and can lead to stressful situations.
It is important for us to discuss the topic comprehensively with you, to answer all your questions and to respond to your doubts and concerns.
Polar body diagnostics (PBD)
Shortly after the sperm has penetrated into the egg shell, the egg cell forms two polar bodies. These are no longer needed later and die. They contain DNA copies of the nucleus.
For the examination, we take both polar bodiesbefore the embryo develops. By diagnosing these genetic copies, not the nucleus, we clarify whether the woman has genetic disorders, genetic defects or structural chromosome disorders.
It is not possible to determine sex or to analyze male genetic material.
At the time of removal of the polar bodies, egg and sperm cells have not yet fused together. There has not been any fertilization. Therefore, the eggs are artificially fertilized by injection of each sperm (ICSI) and further developed during the period of the polar body examination. The examination takes about three days. Then we select those embryos for the transfer, which originated from the genetically suitable oocytes. Since the examination takes place before fertilization, the polar body diagnosis is ethically less controversial than the other methods of preimplantation genetic diagnosis. The method is error-prone, because "only" the copy of the female genome is examined. It also allows no statement about the male genome.
Trophectoderm biopsy (TOBI)
The trophectoderm biopsy takes place after the fertilization. The embryo develops on day 5 or 6 after fertilization to a so-called blastocyst, a germinal vesicle. For the examination, we take a few cells from this blastocyst. The embryo core, from which the child develops, remains untouched. The taken trophectoderm cells play no role for the further development of the embryo. For the genetic examination, we freeze the cells taken. Their examination allows to detect changes in the genome and to exclude affected embryos from transfer to the uterus.
In Austria the trophectoderm biopsy has been allowed under certain conditions since February 2015:
If three IVF / ICSI attempts were unsuccessful and there is reason to believe that the failure is due to the genetic disposition of the embryo.
If three stillbirths or miscarriages have occurred after artificial insemination. These are likely to be due to a genetic disposition of the embryo.
If a genetic disposition of at least one parent increases the risk of stillbirth, miscarriage or hereditary disease of the child. A hereditary disease is defined as follows:
The child can only be kept alive by the constant use of modern medical technology.
The child can only be kept alive by the constant use of other medical or nursing aids which seriously affect their way of life.
The child will have severe brain damage.
The child will eventually suffer from severe pain that, like the disease itself, is untreatable.
Choice of the sex of the child is prohibited unless there is a risk of hereditary disease connected to the child’s sex.
The trophectoderm biopsy is primarily used when a miscarriage or stillbirth or a specific hereditary disease should be avoided. By choosing the genetically most appropriate embryo, it helps to shorten the time to a healthy pregnancy (time-to-pregnancy).
"Every couple wishes for a healthy child. Preimplantation genetic diagnosis helps to select the most viable embryo. "
In genetic diagnostics, the experts assume that all cells of a blastocyst carry the same set of chromosomes.
In recent years there are increasing suspicions that the so-called euploid cells - cells with a complete set of chromosomes - are located more in the embryo nucleus, which is thepart of the embryo from which the child develops. Non-euploid (aneuploid) cells are likely to occur more in the trophoblast, which are the cells that are examined by trophectoderm biopsy. If the cells taken by biopsy are euploid, it can be concluded that this also applies to the embryo. If aneuploid cells are detected, the situation remains a bit unclear. It may or may not be the case that the embryo is affected as well.
There is a hereditary disease in your family? You had several unsuccessful attempts of IVF treatment? Arrange an initial meeting with us. We will inform you in detail about the methods of preimplantation genetic diagnosis and the possibilities of artificial insemination.
With the pre-implantation diagnosis, we clarify whether your eggs or embryos are healthy. It allows us to select specific unencumbered oocytes or embryos and to avoid genetic defects in your baby.
PID can be carried out on oocytes and embryos.
Precondition for the pre-implantation diagnosis is that an artificial insemination (IVF, ICSI) takes place. The examination takes place outside the body, even before we transfer the embryo into the uterus.
We differentiate in polar body diagnosis (PCD) and trophectodermbiopsy (TOBI). In polar body diagnosis, we clarify whether genetic disorders, genetic defects or structural chromosome disorders are present in women. The Trophektodermbiopsie is primarily used when a miscarriage or stillbirth or a specific hereditary disease should be avoided.
The choice of sex is decidedly excluded. Besides, the feared hereditary disease is related to the sex of the child.
The investigations serve to select the best genetically suitable embryos. This increases the likelihood that the embryo is healthy.
Yes, because the most genetically suitable and fittest embryos are selected.