With the continuous advancement of IVF technology, the technology has gradually become the best way to treat infertility, and has also begun to be accepted by the majority of infertility patients, so far, IVF technology has been developed to the third generation, that is, the PGD and PGS technology that we often see. But what's the difference between the two? Please take a look at hengjian overseas for details on this.
First- generation, second- and third-generation IVF technology features:
The first generation of IVF (IVF) addressed infertility caused by female factors.
Second-generation IVF (intracytoplasmicsperminjection) (ICSI intraplastic intraplastic injection) addresses male-induced infertility.
Pre-implantation geneticscreening(PGS preimplantation screening) helps humans choose to produce the healthiest offspring.
Introduction to IVF 3rd Generation:
Third-generation IVF, also known as preimplantation genetic diagnosis (PGD), refers to the method of taking the genetic material of the embryo before the ivf-ET embryo transfer, diagnosing whether there is abnormality, screening healthy embryo transfer, and preventing the transmission of genetic diseases.
The test material takes 1 cell of 4 to 8 cell stage embryos or the first and second polar bodies of the egg before and after fertilization. Sampling does not affect embryonic development. Single-cell DNA analysis is used for detection, one is polymerase chain reaction (PCR), to detect male and female sexes and ungene genetic diseases; The other is fluorescence in situ hybridization (FISH), which detects sex and chromosomal disorders. Edwards proposed the idea of PGD as early as 1964.
Introduction to PGD and PGS:
PGD (preimplantation genetic diagnosis), the pre-transplant genetic diagnosis, is the third generation of "test tube babies". It is mainly used to check whether embryos carry genes that are genetically defective.
It is mainly used to check whether embryos carry genes that are genetically defective. It is based on IVF technology, sperm eggs in vitro binding to form a fertilized egg, and after developing into an embryo, genetic testing is carried out before it is implanted in the uterus, so that IVF in vitro in vitro to avoid some genetic diseases. At present, preimplantation genetic diagnosis can diagnose some diseases caused by single gene defects, such as hemophilia, thalassemia and other diseases, which can be directly detected through such diagnosis.
PGS (Preimplantation Genetic Screening) refers to the preimplantation genetic screening, when the embryo implantation bed, the early embryo is detected for the number of chromosomes and structural abnormalities, by a one-time detection of the structure and number of 23 pairs of chromosomes of the embryo, to analyze whether the embryo has genetic material abnormalities of an early prenatal screening method. In this way, normal embryos are selected for implantation in the uterus in order to obtain a normal pregnancy, improve the clinical pregnancy rate of patients, and reduce multiple pregnancies.
What is the difference between third-generation IVF PGD and PGS?
PGS is pre-transfer chromosomal screening, while PGD is pre-transfer genetic diagnosis.
PGD: PGD genetic diagnosis determines whether an embryo carries a mutation in a gene that may lead to a specific disease, a gene that is a fragment of DNA on a single chromosome.
If a gene abnormality occurs, it may cause the child to develop specific diseases, such as cystic fibrosis, thalassemia, Down syndrome, cat syndrome, etc. If both parents are known to be carriers of the disease, they may inherit the disease to the next generation in the future.
PGD tests are performed in the same way as PGS, but laboratories do not examine chromosomes, but specific genetic mutations, a way that can currently diagnose up to 125 recessive diseases.
For people with a specific genetic history, PGD can help high-risk couples avoid passing on major genetic diseases to the next generation, giving them the opportunity to have a healthy offspring, and avoid the frustration and pain of having to terminate pregnancy due to genetic disorders found in traditional prenatal checkups.