Sex can lead to urinary tract infections. There are already a lot of bacteria in the female perineum, and the vaginal and urethral openings are very close to each other, so the inevitable squeezing that occurs during sex can easily bring bacteria to the female urethra. Due to the friction will also cause damage to the mucous membrane of the female urethra, so that the mucous membrane resistance decreases, easily causing bacterial infections. If the female patient has other gynecological inflammation, urinary tract infections can easily occur during sex. For men, if they do not clean their external genitalia in time before sex, especially men with long foreskin, it is easy to transmit bacteria to women, thus causing urinary tract infections. Both male and female patients need to wash their pubic area frequently, pay attention to personal hygiene, and if recurrent urinary tract infections occur after sex, they need to prohibit sex for a period of time, drink more water, and apply antibacterial medication than oral levofloxacin.