The first generation of IVF: This technology is mainly for patients who have blocked fallopian tubes or had their fallopian tubes removed due to disease, where sperm and eggs cannot meet inside the body. This technology allows sperm and eggs to complete their union outside the body to form a fertilized egg, which can be cultured and developed until the right time and sent back to the uterus for the woman to conceive. Second generation IVF: This technology is mainly for men with severe weak sperm vitality or low sperm count, or even no sperm. After the sperm is retrieved through male surgical techniques, a single sperm is injected into the follicular plasma and the fertilized egg formed is then transplanted back to the uterus at the right time, thus conceiving. This means that the second generation of IVF is not more advanced than the first generation. The first and second generation of IVF are for patients with different indications and are two different technologies. The first generation of IVF focuses on female infertility patients, and is suitable for women with tubal obstruction, tubal agenesis, loss of function after tubal surgery, refractory ovulation disorders, endometriosis that does not result in pregnancy after general treatment, mild oligospermia in the male partner, and unexplained infertility, all can take the first generation of IVF technology; while the second generation of IVF focuses on male infertility patients, such as severe oligospermia, weakness, teratospermia, and unexplained infertility. The second generation IVF focuses on male infertility patients, such as severe oligo-, oligo- and teratozoospermia, irreversible obstructive azoospermia, etc.