Appropriate masturbation does not cause harm to the body and need not be overly concerned. However, excessive and frequent masturbation may cause urinary tract infection, lead to male infertility, lead to penile sensitivity, affect the mental state and so on. 1. cause urinary tract infection: long-term frequent masturbation, may lead to bacteria into the urethra, resulting in urinary tract infection, serious will also cause prostatitis, seminal vesiculitis, and so on. 2. lead to male infertility: long-term masturbation makes male ejaculation frequency greatly increased, sperm quality decline, serious cases may lead to normal sexual life male can not ejaculate or sperm volume is very small, cause male infertility. 3. lead to penile sensitivity: men often masturbate in order to only seek a quick and take a simple and rough way, each masturbation may cause different degrees of damage to the penis, long-term may lead to penile oversensitivity and cause premature ejaculation. 4. affect the state of mind: long-term masturbation will also affect the state of mind of men, so that they lose vitality, the whole day decadence and fatigue, and some will also appear the symptoms of memory loss. The excessive masturbation person should go to the hospital in time to seek medical treatment.