Women’s underwear should be changed once in 1-2 days, because wearing underwear for a longer time can easily cause bacterial contamination and vaginal inflammation. For younger women with more secretions, you can change your underwear once a day, if you are older you can change your underwear once every 2 days, but it is relatively hygienic to change your underwear once a day. In addition to changing underwear, you should also pay attention to keeping your vulva clean and hygienic, and to the hygiene of your husband and wife during intercourse and menstruation. Wash your vulva every day, and wash your underwear with boiling water and expose it to the sun to disinfect it. If you are suffering from vaginitis, your underwear will be easily contaminated during the treatment period, so you should change your underwear even once in half a day. Therefore, the specific time for women to change their underwear depends on their own situation and from a hygienic point of view, without gynecological inflammation it is recommended to change underwear once every 1-2 days.