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PGS: Identification and treatment of Genetic Disorder

What are Chromosomes? How they help us to decide genetical identity? And also, why women need to undergo PGS during IVF? Does PGS help to identify genetical disorder in natural pregnancy as well? We have answers to all your curiosity !!


Chromosomes play avital role in the human body. Chromosomes are two types one is autosome and another one is allosome. Both are sex chromosomes. In human body, there are 23 pairs of chromosomes. Further, these chromosomes are divided into X and Y. If an egg is fertilized by an X-bearing sperm, the resulting embryo will have two X chromosomes (XX), and will grow into a baby girl. If a Y-bearing sperm fertilizes the egg, the embryo will have XY chromosomes, a boy. (Except in the rare case of testicular feminization.) Since men’s sperm carry both male and female chromosomes (Y & X) in 50:50 proportion, and women’s eggs carry only one female chromosome (only X, because her sex chromosomes are XX), the man’s sperm holds the key to a baby’s gender.The main function of the chromosome is to pass progeny and genetic material from parents to the child that is related to a particular organ of the parents.


When we start the procedure of IVF, the PGD is performed to examine genetical disorder. This test is executed just before the implantation of Embryo. This procedure is performed on the 5th day of fertilization known as a blastocyst. At this blastocyst stage embryologists perform the biopsy of the embryo to confirm the total number of chromosomes. The total number of the chromosomes should be 46, which are the normal number of chromosomes. After this particular stage with the help of innovative technology, the total number of chromosomes is confirmed within each cell.


There are two kinds of cells found after the blastocyst stage.


  • Euploid that contains a normal number of chromosomes
  • Aneuploid that has an abnormal number of chromosomes


PGS is performed to avoid abnormal embryo transfer in the uterus. If the doctor is transferring the embryo in the uterus of the women then it should be confirmed that the embryo is normal and is containing all 46 chromosomes.


Basically, PGS (Preimplantation Genetical Screening) or (Aneuploidy Screening) that comprises the examination of the embryos conceived by IVF or ICSI. This procedure is utilized to recognize common abnormalities. These abnormalities majorly cause the failure of embryos to implant and of miscarriages or abortions.


PGS is recommended to those IVF or ICSI patients if:


  • If the patient has crossed the age of 40 and is diagnosed with the higher risk of having a child with any chromosomal problem.
  • If the patients are having the history of genetical or chromosomal problems.
  • If the women has a history of miscarriages or abortions.
  • If a healthy embryo has been transferred to the patient and still IVF outcome of the patient is not successful.
  • If the sperm of the male partner is also diagnosed at high chromosomal risk.


Benefits of PGS


  • PGS is improving the implantation and pregnancy rate during IVF.
  • PGS helps to increase the live birth rate.
  • All the improvements are possible due to PGS and this process allows to transfer embryos without any genetic disorder.
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