What is azoospermia? Azoospermia refers to the absence of sperm in the semen. Its diagnosis requires that no sperm is seen in the semen of more than 3 consecutive routine semen examinations and that no sperm can be found under a microscope after centrifugation of the semen. Patients with azoospermia account for about 10% of the male infertility population and are the most serious type of male infertility, theoretically unable to produce their own offspring through natural conception and being absolutely male sterility. The reason for azoospermia is that it accounts for 10% of male infertility, and the lack of effective treatment in the past. There are many causes of azoospermia, mainly divided into three categories: first, pre-testicular factors, mainly reproductive endocrine abnormalities, such as hypoprolactinemia and hypogonadotropic hypogonadism in hypothalamic or pituitary lesions, which are often accompanied by abnormal development of male secondary sex characteristics and reproductive organs; second, testicular causes of spermatogenic dysfunction, such as chromosomal number abnormalities in Creutzfeldt-Jakob disease, secondary to adolescent mumps The third is post-testicular causes, that is, obstruction of the vas deferens, resulting in the inability to eliminate semen from the body, also known as obstructive azoospermia, the site of obstruction can be at the level of the epididymis, vas deferens or ejaculatory duct, the most common of which is congenital bilateral absence of the vas deferens, while secondary to the reproductive drainage duct It is also more common to have obstruction due to infection. What tests are needed in patients with azoospermia? The diagnosis of azoospermia is complex, and it is important to recognize the cause of the disease through detailed examination and diagnosis. Our experience is that after determining the absence of spermatozoa through semen examination, we first perform an examination of male sexual characteristics and reproductive organs to initially identify whether it is a lesion of the testes or the vas deferens. When obstruction of the vas deferens or epididymis is considered, a qualitative semen fructose analysis should be performed to initially identify the site of obstruction, or a vasovasography should be performed under anesthesia to further clarify the site and degree of obstruction, and if necessary, vasovasal and epididymal explorations can be performed to try surgical reconstruction of the duct at the same time while making a clear diagnosis. When considering testicular lesions or pre-testicular etiology, relevant endocrine hormone measurements, mainly follicle stimulating hormone (FSH), pituitary prolactin (PRL) and testosterone (T), should be performed to determine whether there are hypothalamic, pituitary or testicular lesions, and to determine the extent of testicular damage. Finally, consider whether a testicular biopsy can be performed to clarify the spermatogenesis within the testes and to guide the next step of treatment. Is azoospermia treatable? Twenty years ago, it was basically impossible for azoospermia patients to have their own offspring, but with the mature application of modern assisted reproductive technologies, especially the second generation IVF technology, intrafollicular single sperm injection (ICSI), and the widespread implementation of minimally invasive microsurgery, the treatment of azoospermia has been greatly improved. For patients with azoospermia due to endocrine hormone disorders, sperm production can be restarted and increased by removing the lesions and exogenous gonadotropin supplementation, and some patients can even obtain their own children through natural conception. For azoospermia caused by obstruction, because the spermatogenic function of the testes is intact and there is a large amount of mature sperm in the testes, after reconstructing the vas deferens by surgical means, the sperm can be discharged normally and the chance of conception can be regained; even if some patients are unwilling or unable to reconstruct the vas deferens, they can still obtain their own children through testicular sperm retrieval – ICSI assisted conception. In the case of azoospermia due to testicular causes, if mature sperm can be found through testicular biopsy, testicular sperm retrieval-ICSI can also be used to help conceive; if no sperm exists in the testicles, although there is no effective treatment, patients can have their own children in the legal and ethical sense through donor-assisted reproduction or adoption. The skillful development of a large number of modern male minimally invasive microsurgeries, such as vasectomy microanastomosis and vas deferens-epidididymal microanastomosis, has greatly improved the post-operative vas deferens recanalization rate, and the vasectomy microanastomosis recanalization rate in our center is now even up to 100%. The newly introduced testicular microscopic sperm retrieval technology, which has the advantages of less surgical trauma, high sperm acquisition rate and less postoperative complications, is gradually and widely carried out, making the outcome of azoospermia treatment much improved and more and more azoospermia patients have their own children. How can you avoid and detect the presence of azoospermia as early as possible? First of all, we have to pay attention to the development in infancy and early childhood, especially to the testicular descent, and solve the problem of cryptorchidism before the age of 2; while in adolescence, we have to pay attention to the development of secondary sexual characteristics and external genitalia, and prevent the testicular dysplasia and developmental delay caused by reproductive endocrine disorders. At the same time, the inflammation of the reproductive system should be actively dealt with to avoid inflammatory obstruction of the vas deferens. Crude raw cotton oil can cause damage to spermatogenic cells and testicular atrophy, so it should be avoided. Finally, it is recommended that men undergo routine semen testing before marriage to make a preliminary determination of fertility.