Male infertility is the inability of a couple to have children after more than one year of living together without contraception due to male factors. In terms of the reproductive process, there are three components that determine whether a man can have children: whether the man can get sperm into the woman’s vagina; whether sperm can reach the fallopian tubes through the uterus and meet the egg; and whether sperm can drill into the egg to complete normal fertilization. Then, a problem in any part of this complex process can lead to a result we don’t want to see – infertility. Let’s look at the above links to discuss the possible causes of male infertility and the traditional treatment options. The first is the male partner’s ability to have sperm enter the female partner’s vagina, both in terms of the ability to deliver sperm into the vagina and the presence or absence of sperm. The former is more common in patients with erectile dysfunction, genital malformations, non-ejaculation and retrograde ejaculation who share the common feature that they can have normal sperm but do not have the ability to send sperm into the vagina. The latter can be divided by cause into two categories: non-obstructive and obstructive. Non-obstructive patients have impaired sperm production in the testes and are unable to produce sperm, while obstructive azoospermia is due to blockage or absence of the vas deferens, which prevents sperm from being discharged from the testes. According to traditional treatment, some of these patients can be made fertile through surgery, medication and artificial insemination (AIH); some may only be able to obtain “offspring” through artificial insemination by donor insemination (AID) or adoption; but some others will not have the next generation. The next question is whether sperm can reach the fallopian tubes through the uterus and join the egg. When the sperm enters the vagina, it first passes through the cervix into the uterus and then travels down the curved fallopian tube to join the egg in the abdomen. This “long journey” requires a high degree of stamina to reach the end of the line and a certain speed. If you do not arrive within a certain time, you will lose the opportunity to rejoin the egg, so when there is no sperm to rejoin the egg, a normal woman cannot get pregnant. Clinically this usually manifests as severe oligospermia or weak spermatozoa. Routine semen examination usually shows a small number of sperm or occasionally motile sperm under high magnification, these sperm are basically lost on the way because the number is too small; or the number of sperm is normal or near normal, but the motility is very poor, basically no forward motion or very slow motion, and you will not be able to reach the “end point”. The treatment of these patients is generally based on Chinese and Western medicine medication, but the results are very unsatisfactory and only a small number of patients can have their own children. The final step is the possibility of having sperm drilling into the egg to complete normal fertilization. The sperm reaches the end of the line at a certain point and joins the egg, at which point the final job of the sperm is to drill into the egg. If we compare the egg to the size of a ping-pong ball, the sperm is about the size of a sesame seed. The sperm has to pass through the outer radial crown of the egg, the zona pellucida of the egg and the cytoplasmic membrane of the egg before it actually enters the egg. The dense radial crown at the periphery of the egg requires many sperm to work together to secrete an enzyme called hyaluronic acid to loosen it, so this step cannot be completed without a certain number of sperm. It is then that the sperm have the opportunity to approach the zona pellucida and use the acrosome of the sperm head for the final “battle”, which is only possible if the acrosome of the sperm is abnormal. Once a sperm has passed through the zona pellucida, the zona pellucida hardens itself and rejects the rest of the sperm. The incoming sperm are lucky enough to complete fertilization with the egg. Obviously, without the “sacrifice” of a certain number of sperm with good motility, normal function and normal morphology, it is impossible for the luckiest sperm to complete this complex process. So, how many sperm are there to make it possible? The World Health Organization has developed a standard based on years of research by many scientists: the normal semen ejaculated by men should be 2-6 ml, and there should be no less than 20 million sperm per ml of semen, of which more than 50% should be forward-acting sperm, and more than 30% should be sperm with normal morphology. This is what we call the basic requirement of normal semen. For patients who cannot reach this standard, the treatment method and effect is relatively good, after looking for the cause of oligozoospermia, the first drug treatment; can also be artificial insemination, semen in vitro washing directly into the uterine cavity, not only to remove the sperm unfavorable factors in the semen, increase the vitality of the sperm, but also to shorten the sperm “march” It has a high success rate. However, there are still some patients who cannot solve the problem completely. The year 1992 was a time of dawn for the above-mentioned patients who could not see hope in several stages. Scientists in Belgium, after years of work, completed the world’s first intra-ovarian single sperm puncture based on IVF technology, allowing an unlikely male to have his own offspring. This technique involves injecting a sperm directly into the cytoplasm of an egg under a 200-400x microscope using sophisticated instruments to complete fertilization, and then placing the fertilized, well-developed embryo directly back into the wife’s uterus. In just a few years, millions of couples have been the beneficiaries of this technology. China’s first intra-ovarian single sperm puncture baby was born in 1996 at the Sun Yat-sen Medical University in Guangzhou, and now, nearly 100 IVF centers in China perform this technique. Let’s go back to the three links above to see that the early intra-ovarian single sperm puncture technique was mainly for patients with sperm in their semen, and later developed to the point where all patients who have undergone conventional treatment above can technically be treated with intra-ovarian single sperm puncture as long as they have sperm in their testes, including obstructive azoospermia. Nowadays, we can simply perform a simple testicular fine-needle aspiration and aspirate a small amount of testicular tissue, and if there is sperm, it can be cryopreserved after isolation and later thawed at any time for intra-ovarian single sperm puncture. Nowadays, there are many patients, especially those with azoospermia, who are very interested in this technique, but delay whether the offspring of this technique are normal and whether they will have deformities and mental retardation. According to the results of the nearly 200 cases of intra-ovarian single sperm puncture that I have performed and a large amount of information from home and abroad, the IQ, malformation rate and incidence of genetic diseases in the offspring of this technique are the same as those of normal IVF, and there is no difference between them and babies delivered at normal conception. However, there is one thing that we need to clarify about this technique, and that is that the defects of the father that cannot give birth normally may be passed on to the offspring, which means that the offspring may also have to give birth through this technique, which we call “intra-ovarian single sperm puncture family”. We should see that modern science and technology are developing so rapidly that in a few years, these genetic diseases may be eliminated by genetic level treatment, and our current concerns will be superfluous. In summary, intra-oval single sperm puncture is a new era in the treatment of male infertility and can be a boon to many families without offspring due to male problems, but the clinical pregnancy rate of this technique is generally around 40% and is relatively expensive, making some patients look forward to the emergence of more satisfactory assisted reproduction techniques.