Normal sperm morphology should be 70-80%, and sperm motility can be divided into four grades: Grade A means that sperm motility is excellent and moves forward quickly and linearly; Grade B indicates that sperm activity is very good and it goes straight ahead; Grade C indicates that sperm motility is average, and it only advances in a curve; D-level means that sperm has poor fluidity and can only squirm in situ. Fast-forward sperm and slow-forward sperm (A +b) are less than 50% or Grade A sperm is less than 25%. ① Mild asthenospermia means that A +b sperm is less than 50%, but > 30% or A sperm is less than 25%, but > 65438+. Among them, A-level sperm < 10% ③ Severe asthenospermia means that the number of B +c-level sperm is less than 30%, of which A-level sperm is zero. In asthenospermia, sperm can't move forward, and it is difficult to pass through the cervical canal and uterine cavity and directly reach the fallopian tube to combine with the egg, resulting in low fertility. The common causes of asthenospermia are: 1. Testicular spermatogenic epithelium is not fully mature or mature. 2. Less semen; 3. When seminal plasma changes, such as epididymis, seminal vesicle and prostate inflammation, pH, oxygen supply, nutrition and metabolism are not conducive to sperm activity and survival; If there are anti-sperm antibodies, sperm will agglutinate and lose their mobility.