The success rate of IVF is high when the technology is mature. The traditional treatment is to let patients take ovulation drugs, inject ovulation needles, or do manual irrigation and artificial insemination. The success rate can only be about 15~20%, but it is more difficult to conceive because of the delayed childbearing age of women. It was not until the emergence of IVF technology that it was perfected. IVF fertilized * * * and eggs in vitro by natural culture or microinjection, and selected embryos with better types to be cultured and implanted into the mother. Generally speaking, the success rate is around 50%. However, some of these better types of embryos can't be successfully implanted and pregnant because of chromosomal abnormalities, so it is difficult to distinguish them in appearance, and it is necessary to rely on chromosome gene screening (PGS) before implantation to assist the screening.
The key reason of recurrent abortion is abnormal embryo chromosome. Dr. Pan Shibin mentioned that many female friends who come for help have had more than two pregnancies and miscarried within 6 to 8 weeks, which is clinically called repeated abortion. The key causes of recurrent abortion are * * * and poor egg quality, which leads to abnormal chromosome number and embryo development defects. Other reasons include: living habits, obesity, immune system problems, uterine environment, ovarian and endocrine problems (luteinizing hormone deficiency, abnormal secretion of thyroid hormone and adrenocortical hormone), vascular thrombosis or inflammation (related to immunity) affecting placental nutrition supply, which may cause repeated abortion or pregnancy difficulties.
Chromosome gene screening (PGS) before embryo implantation is helpful to improve the success rate of artificial pregnancy. It is impossible to predict whether the chromosome of the fertilized egg is normal before it is combined with the egg. To rule out the abortion caused by chromosome abnormality during artificial conception, we can choose to do chromosome gene screening (PGS) before embryo implantation to improve the chances of successful pregnancy. Dr. Pan Shibin mentioned that in the past, chromosome gene screening (PGS) was done early, and embryos (8~ 12 cells) cultured on the third day after fertilization were obtained from a single cell for chromosome analysis, but a single cell could not represent whether the whole embryo was normal or not, so the reference value was low. At present, a small number of cells in embryos cultured on the fifth day after fertilization (blastocyst stage) are used, because the state of cells is relatively stable, accurate chromosome gene analysis (above 99.9%) can be carried out, and then the best embryos can be selected for implantation. As far as clinical experience is concerned, the success rate of pregnancy has almost doubled. But Dr. Pan does not deny that 1 1,000% can't get pregnant even if the best embryo implantation is chosen. Other physiological factors must be considered, but at least pregnancy failure caused by chromosome abnormality can be ruled out.
Many people think that successful pregnancy through chromosome genetic screening (PGS) before implantation means that the fetus' chromosomes are normal, but this is actually a wrong idea. Because in the process of embryonic development, it is still possible to have uncontrollable mutations. At present, international standards generally believe that pregnant women who are artificially conceived must undergo prenatal chromosome examination. Dr. Pan Shibin suggested that under the dual protection of successful pregnancy, the risk of fetal abnormality can be minimized through chromosome gene screening (PGS) before embryo implantation combined with non-invasive fetal chromosome gene detection (NIFTY/NIFTY PLUS) or invasive amniotic fluid examination (even amniotic fluid chromosome gene chip).
According to statistics, more than 1/3 pregnant women are playful twins. Dr. Pan Shibin mentioned that in artificial conception, fraternal twins account for the vast majority. In the past, if twin pregnant women wanted to do accurate chromosome examination, most of them took invasive amniocentesis. However, there are some clinical published data and documents that confirm that noninvasive fetal chromosome gene detection (NIFTY) can accurately analyze the common chromosomal abnormalities of twins, such as Down's disease (T2 1), Edward's disease (T 18), Bartonella disease (T 13), and the accuracy of identical and fraternal twins. 99%), so that pregnant women with twins can also enjoy the protection of safe birth inspection.
Dr. Pan Shibin, Dean of Shengquan Obstetrics and Gynecology, graduated from the Department of Medicine of Taipei Medical College, postdoctoral researcher of Yale Medical College, attending physician of American Obstetrics and Gynecology/director of infertility department of Ma Kai Memorial Hospital, chairman of Taiwan Province Anti-aging Society, director of the Republic of China Infertility Cultural and Educational Foundation, director of the Republic of China Fertility Medical Association, director of the Republic of China Obstetrics and Gynecology Society, and health care expert of American eugenics.
Learn more about topics: PGS, infertility, genetic testing, genetic technology, fertility problems, prenatal examination.