I am often asked by patients in the clinic why his semen is of poor quality and why his lover is not pregnant when his tests are all good. To be honest, sometimes I can answer these questions, and sometimes I can’t. Today, I am here to talk to you about the causes of male infertility. The causes of male infertility are divided into four categories: 1. pre-testicular factors; 2. testicular factors; 3. post-testicular factors; 4. idiopathic causes. I. Pre-testicular factors. Simply put, in order for the testes to produce sperm, the brain, the commander, needs to give “instructions” – secrete gonadotropins. If these hormones are not secreted enough, the testes will lack the “power” to produce sperm. This type of cause is encountered in clinical practice, but is not common. Second, testicular factors. This type of factor is more common. 1, varicocele is one of the most common, with a prevalence of 35% in patients with primary infertility and 75% in patients with secondary infertility. The treatment options for this disease are very mature and effective, mainly through surgery. In order to better carry out this surgery, I went to the Obstetrics and Gynecology Hospital of Zhejiang University, Renji Hospital of Shanghai Jiaotong University, and Cleveland Medical Center in the United States to study. Now we carry out the spermatic vein microligation, which is basically in line with the most advanced international, less traumatic and fast recovery. Some patients are afraid of surgery, but in fact, it is not necessary. 2.Cryptorchidism. The testicles are not in the scrotum, but in the groin or abdominal cavity. Since the testicles like a “cool” environment, and the internal temperature is higher than the scrotum, the testicles have an obstacle to produce sperm. For this type of factor, there is no need to operate as soon as possible. For inguinal cryptorchidism, general open surgery can complete testicular descending fixation; for abdominal cryptorchidism, the laparoscopic surgery we carry out can also achieve better results. 3.Testicular tumor, trauma and inflammation. Tumor and trauma are “hard injuries” and should be treated immediately once they are found. The danger of inflammation cannot be ignored. Bacteria, viruses, spirochetes, mycoplasma, chlamydia and other infections occurring in the testes can cause damage to the spermatogenic epithelium, spermatogenic cells are shed, and more importantly, the blood-testis barrier is damaged, resulting in no sperm production, or few sperm, weak sperm, and deformed sperm. The infection, if it occurs in the epididymis, causes impaired sperm maturation and impaired energy metabolism, and decreased sperm quality and motility. There is also a special kind of infection. There is a disease called “mumps”, commonly known as “big mouth”, which occurs in children. This disease is very powerful and damages not only the parotid gland but also the testicles. In our male infertility clinics, we often encounter these people who have no sperm as adults. The actual fact is that you must seek medical attention at the time of the disease, once the root of the disease, the future treatment is more difficult. 4. Other. The majority of patients with chromosomal abnormalities, such as Creutzfeldt-Jakob syndrome, have a karyotype of 47, XXY; most patients with an extra X chromosome are azoospermic, and the Y chromosome is missing a segment of the Y chromosome, which can also cause sperm production disorders. Most chromosomal abnormalities are treated with assisted reproduction techniques. There are also many other diseases not listed here. Third, post-testicular factors. This is a disorder that occurs during the transportation of sperm after they have been generated. 1, obstruction of the vas deferens. Blockage of the ducts for sperm transport. This condition is most commonly known as epididymitis. Some patients have had enlargement of the testicles epididymis and sometimes fever. After this disease is cured, there may be sequelae of blocked epididymal ducts left behind. This can be solved by surgery. We have performed microscopic anastomosis of vas deferens and epididymal ducts, which can “unblock” the blocked road again. In addition, vasectomy is also a cause of obstruction. 2. Sexual dysfunction. This is very understandable, if you can not complete the appropriate frequency of sex, or can not ejaculate semen into the spouse, of course, pregnancy will become a problem. Some people live apart and couples spend less time together, which can actually be classified as a post-testicular factor. 3, immune infertility. The male and his spouse’s body may produce “antibodies” against the sperm! Originally, the antibodies are against foreign “invaders” and are a kind of immune defense, but if they occur against sperm, they will affect sperm activity and affect sperm-egg bonding. Idiopathic infertility. This is also known as unexplained infertility. Modern medicine is developing rapidly, but there are still many problems that cannot be solved. Many patients with male infertility, the cause of which cannot be fully explained, we call idiopathic infertility. In fact, such patients are still relatively common, accounting for more than half of all male infertility patients. However, the fact that the cause is unexplained does not mean that it is untreatable. For the vast majority of these patients, effective treatment can be found. The causes are numerous, but in general, with the continuous advancement of medical technology, the majority of patients are able to have their own babies through medication, surgery and, if necessary, assisted reproductive technology. The last thing you need to do is to give your male friends a few suggestions: 1. Avoid smoking and drinking. This does not need to be said. 2, more exercise. The whole person is a whole, the whole body state is good or bad, will affect the sperm production and activity. 3, pay attention to diet. There are some foods that are particularly helpful to male fertility, you can eat more vegetables and fruits. The seafood oysters, tamari, sea cucumber, dried fruit in the sesame, peanuts, walnuts, for fertility are helpful. 4, pay attention to rest. Rest and exercise is not a conflict. Can not be too fatigued, especially important is not to stay up late. 5, wear less tight pants, especially jeans, avoid sedentary, do not take a sauna. I wish you all a good pregnancy!