Some of our patients and friends may think that second and third generation IVF must be better than the first generation, but this is not true. The three generations of IVF are not the difference in the level of technology, but the difference in the way the technology is applied to different patients with different situations. The difference between first and second generation is mainly the way sperm and eggs are fertilized. The first generation IVF technique, also known as conventional in vitro fertilization embryo transfer technique. It refers to the natural union of sperm and egg outside the body to form an embryo that is then transferred back into the uterus, mainly to solve the problem of female infertility. Second-generation IVF technique, which refers to intracytoplasmic single sperm microinjection technique. Due to the low quantity or particularly poor quality of sperm, it is not possible to combine with the egg naturally, and artificial means are needed to help fertilize the sperm and the egg and eventually form an embryo. It is primarily a solution to the problem of male infertility. The third generation IVF technology, refers to the technology of testing the genetics of embryos before implantation. It is mainly for patients with genetic risk, and genetic analysis of the embryos’ chromosomes is performed before embryo implantation, thus effectively preventing the birth of children with genetic risk. Therefore, the choice of IVF technique depends mainly on the patient’s condition. The three generations of IVF techniques are not equivalent nor are they interchangeable.