PGD is a method of determining the genetic characteristics of the embryo before replanting. There are two methods for the diagnosis of the embryo.
First method is biopsy, it’s a removal of a single cell embryo for the research. A biopsy performed on 3 day of embryos life, at this time the number of cells from 4 till 10 and they are not differentiated, identical, interchangeable and remain active at the stage of division. After sampling cells, the embryo must begin to develop more quickly to do not lose the speed of development. That is why we watching him a few days more to be sure. If everything went well, and the embryo is developing normally – it starts taking endometrium mother.
Second method is visual assessment by using embryoscopy. This method of diagnosis is also quite outcoming, but is heavily dependent on the human factor – experience and professionalism of the doctor.
Accuracy of diagnostic are higher by using biopsy but still not 100% garantide. The reason for the error is that sometimes assembled to study cell may have different characteristics than the other cells of the embryo. Scientists says, that he risk fence for blastomere of the embryo is a minimalistic (first addition from 1989, since that time statistic being collected).
PGD is literally translated as “Preimplantation diagnosis”. I.e. It allows to determine the genetic characteristics of embryos before replacing, such as : health, genetic markers, the child’s sex. For example if woman has had repeated miscarriages or fetal fading PGD allows to choose the strongest embryos for replacing. But we must take into account the fact that the probability of successful conception PGD is slightly reduced. According to the research: the success rate of IVF 38-40%, and for IVF with PGD – 25-28%. Therefore, if you are not in a sort of genetic diseases, didn’t have a numerous fading fetus, you are less than 40 years – we recommend to abandon the blastomere biopsy.
But in some cases PGD is the best choice, like:
- Genetic diseases in your family
- You are over 40 years old (the risk of genetic diseases is increase)
- Prevention of rhesus fetus, if the parents blood is not compatible
- If you need to ensure the birth of a child who would be HLA-matched donor for a sick family member (using umbilical cord blood).
The last recommendation rarely used by itself, but overall, if you decide to PGD because of the risk of genetic diseases, and already have children – it is at the same time the opportunity to choose their HLA-matched brother or sister. After all, if you did not collect the stem cells of an older child after birth – the baby’s umbilical cord blood could help them both.