The main factors that determine the success of IVF are: the quality of the embryo, the receptivity of the endometrium and the match between the two. Like the relationship between the seed and the soil, where the embryo is the seed and the endometrium is the soil, the match between the two is the right time to plant the seed. In addition, personal physical health and psychological factors also play a big role in improving the success rate of IVF. Embryo quality Currently, the quality of embryos is mainly evaluated by observing the morphology and development rate of embryos, which is simple and non-destructive. However, it is difficult to predict the developmental potential of embryos with an accuracy of about 60-70%. It is generally accepted that 66-48 hours after insemination, development to the 6-8 cell stage is the normal developmental rate of the embryo. Before transferring embryos, the quality of embryos is taken into account and those with high developmental potential are selected for transfer, but the number of transferred embryos should be limited to avoid the occurrence of multiple births. Improving the quality of embryos starts with improving the quality of eggs and ova, conditioning the body of both partners is fundamental, having a good diet and lifestyle habits, and necessary nutritional supplements to enhance fertility. Endometrial receptivity is the receptivity of the endometrium to embryos. The successful establishment of endometrial receptivity during embryo implantation is essential to ensure successful embryo implantation, but there is no good indicator to assess endometrial receptivity. Currently, the endometrium is clinically assessed by vaginal ultrasound according to the morphology of the endometrium, which is divided into three types: type A: clear endometrial trilinear signs; type B: blurred visible trilinear signs; type C: disappearance of trilinear signs. Pre-transfer hysteroscopy can also exclude abnormal endometrial lesions. In patients with high embryo quality who were not able to have a successful pregnancy after transfer, hysteroscopy is recommended for this group of patients to exclude uterine cavity pathology. The embryos on the 3rd day of transfer and the blastocysts on the 5th day of transfer are needed to match the time of embryo cultivation in vitro with the time of endometrial transformation and to transfer during the implantation window of the endometrium to improve the success rate. Physical condition and psychological state Heavy psychological stress can affect the endocrine level and therefore the success rate of IVF. High psychological stress often makes women nervous and causes disorders in the contraction of uterine muscles, resulting in embryos not being able to lay properly and leading to IVF embryo transfer failure. However, the number one reason for transfer failure is still age! As the ovaries gradually decline with age, the quality of the eggs will get worse and the success rate of IVF pregnancy will drop significantly due to the aging of the egg cells and the chance of chromosomal aberrations is significantly higher. At the same time, age increases, physical quality decreases, pregnancy can be a great burden on the heart, kidneys and liver, and complications increase during pregnancy and delivery in advanced maternal age, and the live birth rate decreases. So. When you decide to have a baby prepare before it’s too late.