Preimplantation Genetic Diagnosis
Preimplantation Genetic Diagnosis (in short, PGD) is an important step of In Vitro Fertilisation (IVF). This genetic test is done to check the genetic composition of the embryos. In fact, such a check on the embryos before IVF leads to identifying the defects, if any of the embryos thereby prevents spreading of the genetic disorders or diseases in the heirs. However, PGD and PGS (Preimplantation Genetic Screening) take place simultaneously and the reason behind the genetic abnormality in embryos may be caused by factors like ageing and others such as the hereditary genetic disease or disorder.
How does PGD work?
Like you, there may be hundreds who would love to know the process of PGD with a view to reassuring themselves on the various aspects of it. After all, knowledge is power to you. In the process, you and your spouse would be able to take an informed decision here. However, the process is simple as detailed below and every in vitro patient has to go through it.
- Egg production: Female partner takes medicines as suggested by the surgeon and those medicines stimulate the ovary for egg production.
- Egg retrieval: The next step is egg retrieval and your surgeon retrieves eggs using the transvaginal needle in the laboratory.
- Egg fertilisation: The surgeon then fertilises the retrieved eggs with sperms adopting the process called ICSI (Intracytoplasmic Sperm Injection). The onus to mention that ICSI is a special form of IVF that is used for treating male-factor infertility.
- Embryo creation and development: On successful fertilisation, embryos are born and nurtured for 5-6 days in the laboratory so that each embryo can develop 200 or more cells before its plantation in the mother’s uterus. This period helps embryos to reach the stage of blastocyst. For your information, blastocyst is the structure of early development stage of mammals.
Interestingly, only a few cells eventually become placental cells from the stage of blastocyst and those are separated using trophectoderm biopsy. To illustrate this further, trophectoderm biopsy is the most common biopsy done on embryos for the PGS. Here, trophectoderm means a layer of cells that exist on the outer edge of a blastocyst and it doesn’t become a part of the foetus. You should know that this biopsy is usually done on the third day of an embryo development when it barely contains 6-8 cells.
However, it is important to mention that PGD isn’t an alternative for the parental genetic testing such as the amniocentesis and cell-free fetal DNA testing during the pregnancy. Instead, PGD works as an extra layer of security for the safety of your baby.
You will be happy to know that we have our own state-of-the-art genetic lab (The first of its kind in India) that is run by our experts 365 days a year under the supervision of our highly qualified and experienced doctors. The uniqueness of our service here is that we have a robust and expert team that has till now delivered a few hundred babies under this process. Meet us at our genetic lab for an advice on the same.