Before catheterization, female patients should thoroughly disinfect the perineal area, the principle of disinfection is from outside to inside, from top to bottom, the specific order should be the suprapubic area, the outer labia, the inner thighs, the inner labia, as well as the urethral region, the anus. The perineum and the anus are relatively unclean areas. When the patient is ready, the first step is to use a disinfectant cotton ball to wipe the pubic bone area of the pubic mound and the outside of the labia, up to the inner thighs, and then wipe the labia minora and the urethral opening after separating the labia majora, and wipe it twice, and then wipe the urethral opening after the second use of the disinfectant cotton ball to wipe the anus downwards. Disinfection requires the use of less irritating disinfectants such as Neosporin or povidone-iodine, and the cotton balls used for wiping should not be reused, especially after disinfecting the anus, and should be replaced with new cotton balls. After disinfection is completed, a sterile towel is then spread for catheterization. Female urinary catheterization should be operated by professional physicians to avoid incomplete disinfection or improper operation, which may lead to urinary tract infection.