About 40% of infertile couples have a male reproductive defect, and 10% of these patients have obstruction of the vas deferens, resulting in the absence of sperm in the semen, or “obstructive azoospermia”. It is important to explain that “azoospermia” is not the same as “azoospermia”, as most patients with obstructive azoospermia can have normal sex and ejaculate. How is it possible that there is no sperm? In fact, it is like a pot of porridge, only that some of the porridge has no rice inside. There are many causes of vas deferens obstruction, including vasectomy (male sterilization), inflammation of the reproductive tract such as epididymitis, and abnormal development of the vas deferens (such as seminal vesicles and vas deferens). Some patients who are more concerned about themselves can even observe the changes that occur after the obstruction of the vas deferens, such as: “Doctor, my semen used to be very thick, but since the swelling down there two years ago, the semen has become as thin as water” “We even conceived once a few years ago, and then tried to ejaculate a few times There was blood in the semen a few times, and the semen ejaculated after that was less and less” “We always have no problems with sex, but the semen is always less, only one or two drops” All these are often manifestations of obstruction of the vas deferens. For obstructive azoospermia caused by developmental abnormalities, fertility is usually assisted by “IVF” technology (testicular biopsy for sperm – intracytoplasmic single sperm injection); while for acquired obstruction caused by ligation or inflammation, surgical repair of the vas deferens can be considered and then natural conception can be attempted or reduced. “The pain associated with repeated testicular biopsies during IVF can be reduced. In 1901, Professor Martin of the University of Pennsylvania anastomosed the vas deferens with an incised epididymis, extending the use of anastomosis to patients with obstruction of the epididymal segment; in 1978, Professor Silber pioneered the use of microscopic techniques to anastomose the lumen of the vas deferens with the epididymal duct, unveiling the development of microscopic vas deferens-epidididymal anastomosis. Since then, the procedure has been continuously improved by microsurgery experts and has resulted in various surgical methods such as end-to-end anastomosis, end-to-side anastomosis, three-stitch sleeve method, horizontal double-stitch method, vertical double-stitch method and double-tube method. Before the widespread use of IVF, the efforts of these predecessors in surgery brought blessings to countless azoospermia patients who desired to have children.