An IVF embryo is like a seed, she/he needs fertile ground (endometrium), sunshine and rain (internal environment) and fertilizer (ovulation) from the gardener for conception. Abnormalities in each of these components may affect the success rate of IVF. Seed: Embryo Quality Embryos are formed by fertilization of eggs and sperm, and embryo quality is closely related to egg and sperm quality. When the mother is too old and has low ovarian function, the quality of the eggs will decline and the quality of the embryos formed may be average or bad. When the male partner has poor sperm viability or a high rate of malformations, this can affect fertilization, and the quality of the embryos will also decline at this time. When one of the couple has chromosomal abnormalities, the embryos formed may carry abnormal chromosomes and the chance of embryonic abortion or spontaneous miscarriage will increase. This shows that the quality of the embryo is mainly related to the egg and sperm. Soil: Endometrium The endometrium, the soil for embryo implantation, is not conducive to implantation if it is too thick or too thin, or if there are other lesions. The thickness of the endometrium that is more suitable for embryo implantation is usually 8-13mm, with uniform echogenicity and no inflammation, polyps, hyperplasia, fluid accumulation or other lesions. If the above conditions are not met, the success rate of embryo implantation may be reduced or the chance of spontaneous abortion may be increased. Rain and sunshine: internal environment The internal environment of the body includes hormones, metabolism, blood flow, etc. Abnormal hormones such as hyperandrogenemia, hyperprolactinemia, or vitamin deficiency, abnormal thyroid function, or abnormal immune system may affect embryo implantation. Fluid in the fallopian tube may poison the embryo or wash out the embryo and affect the implantation. All the above factors that may affect embryo implantation should be corrected before pregnancy. Fertilization: Ovulation Promotion Program Each patient is an individual and any ovulation promotion program should be customized. Choosing an appropriate ovulation protocol based on the patient’s age, ovarian function, weight, years of infertility, and cause of infertility will result in the optimal number and quality of eggs while reducing the occurrence of ovarian hyperstimulation syndrome. A very important factor: age In fact, age is the most primitive factor affecting the success rate of pregnancy. As women’s ovaries age, the quality of their eggs decreases, as does the quality of men’s sperm. There is no magic pill to bring back the old age. When we talk about the right age to get married and have children, it is usually before the age of 35; after 35, the incidence of infertility is much higher, and the incidence of spontaneous abortion and embryonic abortion is much higher. Therefore, it is recommended that women address fertility issues before the age of 35, and if problems are found around the age of 35 they should be seen in a timely manner and should not be expected.