2. It can be judged by the color of sperm. The color of normal male sperm is grayish white or yellowish. If it is milky white or yellow-green, there may be some inflammation. If the sperm is pink or red in color, it is bloody semen, which is common in inflammation of accessory gonads and posterior urethra.
3. Judging from the viscosity of sperm, checking the viscosity of sperm is to contact liquefied semen with a glass rod, which will form semen filaments after being gently lifted. If semen is normal, the length of semen silk should be less than 2 cm.