Case: 30-year-old Huang is ready to have a child, “closed the forest” before he came to the hospital to do a pre-pregnancy examination, semen analysis suggests that the proportion of his normal sperm is only 6% (normal reference value of reproductive laboratory: normal sperm proportion ≥ 15%), was diagnosed as: deformed spermatozoa. Then, what are the reasons for the formation of dyszoospermia? Can malformed sperm cause fetal malformation? The causes of deformed spermatozoa include varicocele, genitourinary tract infection, mumps complicating orchitis, epididymal tuberculosis and so on, which can affect the quality of spermatozoa; the use of hormones or certain chemical drugs, such as anticancer drugs, lisinopaedic, maryland, furan and so on, which can make spermatozoa development immature; exposure of the genital glands to radiation and irradiation, which can cause spermatozoa mutations; prolonged localized hyperthermia of the scrotum, prolonged The long term high temperature of the scrotum localization, long term alcoholism and smoking as well as chromosomal abnormality can make the sperms have aberrations and lead to the increase of malformed sperms. Varicocele is the most common cause of dyszoospermia. Malformations can be caused by intrinsic factors (e.g., chromosomes, genes, etc.), or by the external environment (e.g., viruses, toxoplasmosis, mycoplasma, chlamydia, iodine deficiency and endemic cretinism, heavy metals such as lead, mercury, and benzene, fluoride poisoning, radiation, radiation from household appliances, computers, and cellular phones, atmospheric pollution, food contamination, diseases, and medications, etc.), or more likely a combination of the two. Deformed spermatozoa do not necessarily lead to fetal deformities, the female reproductive tract has the function of survival of the fittest, the sperm will eliminate most of the deformed sperm in the process of passing through the female reproductive tract (about 1:1.4 million), so as to ensure the quality of the sperm that will conceive, so that it can be said that each new life is a one in a million. However, formal treatment is still essential for insurance purposes, and pregnancy should be carried out after the semen has returned to normal. Suggestions: 1, before preparing to have a child must go to the Department of Reproductive Medicine of the regular public hospitals to do a pre-pregnancy examination, found problems timely treatment. 2, can be natural or after treatment can be naturally conceived, never advocate assisted reproduction, in order to ensure the natural human eugenics function. 3.Pregnancy should avoid all factors that may lead to fetal malformation, especially those pregnant women of advanced age and engaged in high-risk industries. 4. Folic acid tablets (0.4mg/day) can be taken orally for 3 months after pregnancy to prevent neural tube malformation.