If you have lived through a stressful or unpleasant experience you may have noticed that a case of bad breath also went along with the ordeal. One person developed bad breath during airplane trips. The halitosis promptly went away after a safe arrival. A woman developed bad breath when a man she was dating made advances. Having to give a speech or take an examination or endure some other stress inducing situation may also bring out a malady, so monitor your emotional state for cues.
Some women have a distinctive and mousy odor associated with the onset of menstruation.
This particularly common in the women who suffer from dysmenorrhea or painful menstruation. The cause is thought to be caused by the rise in estrogen which triggers sloughing of the body's lining tissues, including those of the mouth. More sloughed tissue means more food for bacteria. Usually the woman is unaware of the odor, but is readily apparent to her spouse. Be aware of the fact that some people don't have bad breath at all, but merely think they do.