Is third generation IVF the last straw for recurrent miscarriages? This fatal flaw cannot be ignored!

　　
　　Third-generation IVF is commonly referred to as embryos that have passed chromosome screening, and if there are no problems in the maternal environment, the chances of success after the transfer are higher than the success rate of pregnancy with embryos that have not been screened.
　　But is this really the case? We found an authoritative evidence and share it with you!
　　01Three-generation IVF you may not fully understand
　　We all know that three-generation IVF is subject to chromosome screening, which is actually different, and for different groups of people, the screening is completely different.
　　Triple IVF can be divided into three categories depending on what is being screened:
　　The first type of screening is called PGT-A: this way can check whether the chromosomes of the embryo have more or less chromosomes, and such embryos may lead to miscarriage or birth defects.
　　This technique is mainly suitable for people with advanced age and recurrent embryo abnormalities, and is equivalent to the original PGS technique.
　　The second type of screening is called PGT-M: this way can check if the embryo has a specific single-gene genetic disease, such as thalassaemia, haemophilia, etc. Such genetic diseases may affect the child’s health and life expectancy.
　　A healthy baby without specific gene carriers can be obtained in this way, which is equivalent to the original PGD technique.
　　The third screening method is called PGT-SR. This method can check whether the chromosomes of the embryo are broken or stuck wrongly, which is actually the embryo chromosome balanced translocation screening technique.
　　In addition, spinach, cabbage, mustard greens, leeks, amaranth, bamboo shoots and other foods rich in oxalic acid should not be taken with calcium, because oxalic acid in the intestinal tract can be combined with calcium to form an insoluble precipitate, affecting the absorption of calcium.
　　How to take calcium supplements scientifically during pregnancy?
　　Pregnant mothers have to be tested before they can judge whether they need to take extra calcium supplements or increase the dosage.
　　Scientific and reasonable calcium supplementation needs to determine whether the pregnant mother’s body is deficient in calcium, rather than blindly supplementing.

02 Randomised multi-centre trial of third generation IVF
　　Studies have focussed on PGT-A. As aneuploidy increases the chances of failure of implantation or spontaneous miscarriage, in women with unexplained recurrent spontaneous miscarriages, this technique may help to improve embryo selection and increase success rates.
　　However, there is a lack of clinical evidence as to whether PGT-A improves cumulative live birth rates in women with a good prognosis.
　　This means that for our regular IVF patients who are not of advanced age and for non-chromosomal reasons, that is, those who are not IIIF indications, it is not known whether there is any additional benefit.
　　This study is a targeted study with that in mind.
　　So, this multi-centre, randomised, controlled trial recruited 1,212 infertile women who were entering their first IVF cycle.
　　They had a good prognosis for live birth, as demonstrated by the fact that they all had ≥3 good quality blastocysts and were aged 20-37 years.
　　Couples with known uterine abnormalities or contraindications to pregnancy, or known to be affected by familial diseases requiring genetic screening, or using donor eggs or sperm were excluded.
　　These women were randomised 1:1 to receive either PGT-A or conventional in vitro fertilisation.
　　Three blastocysts were screened by second-generation sequencing in the PGT-A group and three blastocysts were screened by morphological criteria in the conventional in vitro fertilisation group, and were transferred sequentially, one by one.
　　The primary outcome metric of the study was the cumulative live birth rate after up to three embryo transfer procedures within 1 year of randomisation to group.
　　The results found that in the PGT-A group, nearly 70% of the 1809 embryos screened by genetic testing were aneuploid (aneuploidy increases the chance of failure of implantation or spontaneous abortion).
　　The third screening method is called PGT-SR. This method can check whether the chromosomes of the embryo are broken or stuck wrongly, which is actually the embryo chromosome balanced translocation screening technique.
　　Its clinical significance is to detect the presence of chromosomal structural abnormalities such as inversions, balanced translocations and Roche translocations in the embryo.
　　The purpose is to block the inheritance of chromosomal structural abnormalities, which is equivalent to the part of the original PGD technique that detects chromosomal structural abnormalities in embryos.
　　In fact, the latter two are targeted at specific genetic problems, which are the main targets faced by the third generation of IVF.
　　What we are going to discuss today is mainly the first one, for repeated implantation failure and advanced age, whether the live birth rate can be improved by this technique, let’s look at the literature.