What is Preimplantation Genetic Diagnosis or PGD?
Preimplantation Genetic Diagnosis or PGD consists in analyzing the genetics of an embryo before transferring it to the uterus and in that way, only genetically healthy embryos are transferred.
How is PGD performed?
Technically, to carry out the diagnosis, a small part of the embryo (embryo biopsy) is secured either on the third or fifth day (at the blastocyst stage).
Biopsy technique and embryo quality are fundamental to avoid harming the embryo. An experienced embryologist must perform the procedure.
On a routine basis we offer the biopsy on day 5 which permits us to obtain a larger amount of genetic material to study and also only biopsy embryos that are viable.
Once the genetic material is obtained, it is analysed by specific techniques that offer us a highly reliable diagnosis before embryo transfer.
It is fundamental to inform the couple of their possibilities of success according to each case.
At present, the more developed genetic analysis technique is called NGS (Next Generation Sequencing) together with Arrays.CGH have permitted us to achieve a complete and rapid total genetic analysis before embryo transfer.
When should PGD be performed?
- Severe hereditary diseases, that are early-onset and not susceptible to postnatal curative treatment. This is the case of a couple who are both carriers of a mutation such as Cystic Fibrosis or when one of the parents has a monogenic disease like Neurofibromatosis.
- Determination of histocompatibility antigens (HLA) in pre-embryos for third party therapeutic purposes. When a couple has a child with a disease that needs a umbilical blood transfusion or a bone marrow transplant. In this type of treatment, healthy and genetically compatible embryos are sought after so the future child can become his sibling’s donor.
In these cases a background study of the patients and their family members has to be carried out (a research study) in order to look for the possible anomalies of the embryo. This procedure is called genetic diagnosis.
- Abnormalities that can affect the viability of the pre-embryo. This is the cases that correspond to repeated pregnancy loss, implantation failure and advanced maternal age where numerical and structural abnormalities are searched for. This procedure is called genetic screening.
Thanks to the continuous investment in the latest technology, every stage of the treatment is performed at the clinic, which reduces the waiting times and increases the chances of pregnancy.
If the patient decides to interrupt the treatment, we commit to reimbursing the portion of the treatment that has yet to be completed.
The monitoring of the treatment is done in an efficient and secure way, maintaining patient privacy.
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