Yeast, most commonly of the candida albicans species, reside naturally in warm, moist areas, like the vagina. When conditions allow, for
example, when the body's natural
pH balance is upset, yeast
can begin to grow profusely, thus causing a yeast infection.
It is possible to transfer yeast to a sexual partner. Until the yeast are gone, they can take up residence in your urethra and/or mouth and throat (in a healthy adult, oral yeast is very rare).