Your vagina is basically a self-cleaning oven. It keeps itself at the proper pH (acidic, around 4.7) and maintains a delicate balance of natural bacteria. Similar to your gut, the vagina is home to bacteria that peacefully coexist and help protect you against infection. You should never douche, because it not only washes away helpful organisms, but also may carry dangerous bacteria further up the canal. Indeed, douching predisposes you to bacterial vaginosis and the odor that comes along with it. Defeats the purpose, no?