Hygiene. There is no evidence that poor hygiene can lead to cystitis. In fact, some women wash their anus and vagina too much, which may do more harm than good. Too much scrubbing and cleaning may slightly damage your genital skin. Bacteria thrive better on damaged skin. Cleaning or douching your vagina may alter the normal balance of protective mucus, which may allow bacteria to thrive. A common sense approach is to wash your anus and the nearby skin gently once a day with soap and water. Do not scrub and do not douche your vagina.
Wiping your anus from front to back after you pass a stool (faeces) is commonly advised. The logic is that bacteria from your anus will be pushed back away from your urethra, and not towards it.