Sperm morphology of 3.8% may be malformed spermatozoa, caused by reproductive tract infection, varicocele or heredity. 1. Reproductive tract infection: high-risk sexual behavior in daily life can lead to bacterial or viral infections in the reproductive tract, which can easily lead to high sperm deformity rate, resulting in 3.8% normal sperm morphology. 2. Varicocele: Varicocele can be induced by abnormal blood circulation in the testicles of patients. This disease will lead to localized temperature increase and blood stagnation, which may cause abnormalities in the maturation process of spermatozoa, leading to the above situation. 3. Heredity: some patients affected by genetic factors may cause unexplained sperm abnormality, which can also occur when the normal rate of sperm morphology is 3.8%. Long-term application of sex hormones or environmental influences. Only one examination result can not determine the disease, need to be reviewed. Sperm morphology normal rate of 3.8% may also be caused by other reasons, such as long-term smoking, the use of hormone drugs influence, etc., you should go to the hospital in time to clarify the cause of the disease, and choose the appropriate method of treatment.