How Is The Vagina Self-cleaning?

The mucus that the cervix (top of the vagina, leading to the womb) produces, and that may be part of discharge that some women have, effectively neutralises any bacteria that might get up there.  The mucus helps maintain an acid-balance inside the vagina, which prevents bad bacteria from flourishing and causing infection.  Mucus washing out (discharge) contains old discarded cells from the lining of the vagina.

It was fashionable in the past (especially in the United States) for women to think that they should 'douche', or regularly wash the vagina out with water or soap to keep things clean.  In fact, this is irritating to the delicate acid-balance inside the vagina.  It may also actually increase the risk of HIV transmission as cervical mucus is removed.

There is no such thing as a 'normal' level of discharge for all women.  A woman needs to know what's normal for her and to take action if things seem suddenly different.  As a general rule, though, any spotting between periods may be a sign of trouble and is worth taking advice about.