During a sexual activity, the male partner usually ends with a single ejaculation. For this semen that you ejaculate, have you ever carefully observed its properties? Hospital examination of semen is comprehensive and precise, but it requires a high level of technology, and ordinary people cannot do microscopic observation as well as deeper and more comprehensive testing. The self-examination of semen properties can also predict or rule out some reproductive system diseases. Semen is an inevitable condition for male fertility, and any abnormalities will inevitably affect future fertility problems. The importance of semen self-examination should be taken seriously by all male friends. A normal semen is grayish or milky white in color. If a man has been abstinent for a long time, his semen may be yellowish; but if it appears bright red or dark red, it is indicative of damage to the patient’s reproductive tract; if the semen specimen is transparent, it indicates a low sperm density, which may affect fertility. Some people may ask, “Is it normal if semen is yellowish?” This question should be considered from several points of view: firstly, the duration of abstinence, as a long period of abstinence itself can make semen yellowish; secondly, inflammation, for example, if yellowish semen is emitted despite a short period of abstinence, we should consider whether there is an increase in white blood cells (indicating inflammation of the reproductive tract). Of course, this can only be concluded based on the hospital’s examination. Second, the state of liquefaction Fresh semen can be in a thick jelly state, and generally within 5 to 30 minutes semen will liquefy and become a thin state of liquid. At this time, if a small glass rod (cotton swab, bamboo swab, etc.) is inserted into the semen and then lifted up, the length of the semen filament formed will generally not exceed 2 cm. Otherwise, it is indicative of abnormal semen. Current international standards stipulate that semen that is still not liquid after 60 minutes of ejaculation is considered semen that is not liquefied, which usually reflects the poor performance of the prostate and other reproductive organs. Semen consists of sperm and seminal plasma. Normal seminal plasma contains sufficient proteins, enzymes, lecithin vesicles, etc., which play a key role in the process of liquefaction. If these substances are lowered it can lead to semen not liquefying, reflecting the abnormal working condition of some organs. Some semen specimens even contain a large amount of jelly-like particles, which has a serious impact on male fertility. The international standard stipulates a semen volume of ≥2 ml, which is roughly equivalent to the volume of the cap of a beverage bottle. If the semen volume is too low, it can cause low fertility and even male infertility. There are several reasons for this: The inability to occupy a large volume in the vagina after sexual intercourse is not conducive to the upward movement of sperm and thus to the cervix of the female partner, causing infertility. Since semen is alkaline, a low volume of semen cannot adequately neutralize the acidic secretions in the vagina, which in turn affects the survival and vitality of sperm. Low semen volume can lead to a lower total number of sperm, which decreases the chances of conception. In addition, since seminal plasma is mainly composed of seminal vesicle fluid and prostate fluid, etc., seminal vesicle fluid contains fructose components that provide energy for sperm activity; prostate fluid also provides nutrition for sperm. When the amount of semen is too low to maintain sufficient nutrition for sperm, it affects metabolism and sperm activity and can lead to infertility.