In our clinic we use many other complementary techniques to our assisted reproduction treatments, always aiming to increase the possibilities of pregnancy and for those cases in which the circumstances make it difficult.
At Amnios in Vitro Project, we make the latest medical technologies available to our patients, which allows us to offer the highest possible guarantees of successful treatments, always with a humane relationship which is 100% personalised and where your well-being and the success of your treatment are the only important matter.
Pre-implantation genetic diagnosis is an assisted reproduction technique that allows avoiding transmission of diseases produced by genetic anomalies. This consists of analysing the embryo from a genetic point of view before transferring it to the uterus.
Through PGD, couples who suffer from or are carriers of any of these diseases can have the possibility to have healthy children, free of this disease. They also avoid the his disease continuing to be transmitted to their offspring.
Basically, there are three types of genetic analyses to carry out PGD: FISH (Fluorescence in situ hybridization), PCR (Polymerase chain reaction) and CGH (Comparative Genomic Hybridization). The most used technique is FISH, although each has different aims.
The steps in an IVF treatment using PGD are:
The first step for a PGD cycle is IVF. All the steps are the same, up to the fertilisation of the egg cells. After that, the embryos are observed during their first days of development. PGD is normally carried out on the third day, although this may also be done in the blastocyst stage.
The second phase of PGD is a biopsy of the embryo. On the third day of the embryonic development, when the embryo has between 6 and 8 cells, a biopsy is done, taking just one cell from the embryo, which is then analysed with the corresponding genetic technology. In some cases, the biopsy may be carried out on day 5 (trophoblast biopsy).
The third step is the genetic study of the embryo cell:
- Using FISH anomalies of the number of chromosomes may be detected (aneuploid, like Down syndrome), translocations, etc.
- Using PCR diseases caused by a molecular pathology can be detected, i.e. they occur because a certain molecule is affected. This way it is determined if the embryos suffer from diseases like Huntington’s disease, haemophilia, etc.
- Using CGH it is possible to analyse the complete content of the DNA of the cells, because we can compare the cell with a “master” cell and see if the DNA that the studied cell contains, is the same (which would give us a normal diagnose), greater, or smaller (which would be anomalous).
Testicle biopsy is a technique which allows us, through an intracytoplasmic micro-injection of sperm cells, to obtain pregnancies in couples with men that do not present any sperm cells in the semen analysis. In some cases, after carrying out a semen analysis, we find that there are no sperm cells present in the semen. This is what we call azoospermia. Normally we confirm this result doing another analysis on another semen sample. If in the second sample we find the same result, we then confirm the diagnosis of azoospermia. The causes of the lack of sperm cells in the semen can be many, but we can classify them in two groups:
- Obstructive azoospermia: The testicle produces sperm cells normally, but there is some kind of obstruction in the tracts through which the sperm cells should normally be ejaculated. They are “”.
- Secretory azoospermia: The testicle does not produce any sperm cells due to some kind of problem with the germ cells.
A complete medical examination is necessary and some complementary tests (hormonal determinations, testicular ultrasound, etc.) to complete the study in these cases.
In cases of obstructive azoospermia, those where the obstruction is posterior to the testicle, it is possible to recuperate sperm cells directly from the testicles through a testicular biopsy. Normally sufficient cells are obtained to be able to complete an IVF cycle using the micro-injection technique (ICSI).
The endometrium, i.e. the layer lining the interior of the uterus, is receptive to the implantation of the embryo during approximately 3 days. This period is also known as the implantation window. In a natural cycle this occurs between days 5 and 7 after the ovulation.
In certain cases of implantation failures this could be due to the fact that in some women, this implantation window has been moved. By taking a sample of the endometrium a genetic study can be carried out to determine the state of receptivity. Using this endometrial study, we can thus personalise the implantation window in each woman and increase the possibilities of gestation at the point of transferring the embryo.
In certain cases, like implantation failures, repeated miscarriages or alterations of the male factor, it is deemed convenient to determine the chromosomal composure of the sperm cells through FISH (Fluorescence in situ hybridization). Usually 5 chromosomes are analysed: 13, 18, 21 and the X and Y chromosomes.
If the proportion of sperm cells with an anomalous chromosomal composure (aneuploid) is above the limits that are considered normal, there is a higher risk of obtaining embryos with chromosomal alterations and therefore, with less chances of implantation, a higher risk of miscarriage and even the possibility of having a baby with a chromosomal alteration.
In those cases of an abnormal FISH, pre-implantational genetic diagnosis (PGD) of the embryos would be recommended in order to determine their chromosomal composure, before they are transferred to the uterus.