ANNOUNCER: Because of the vaginal symptoms of yeast infection, many women think it's a sexually transmitted disease. But though there may be a few cases where an infection is linked to sexual activity, the condition almost always appears on its own.
DAVID ESCHENBACH, MD: Yeast infections are not in the general category of sexually transmitted diseases, even though they can be occasionally transmitted sexually. Just simply because the vast majority of the infections come from the woman herself, who then from either changes in her environment or other changes, it occurs spontaneously, allow the yeast to overgrow and cause symptoms.
ANNOUNCER: Yeast infections are usually caused by changes in the vaginal environment, which allow naturally occurring yeast to grow excessively in the vagina. In a small number of cases, the infection may be transmitted by a man
WILLIAM LEDGER, MD: I think if a woman is having unprotected intercourse with an uncircumcised male who has balanitis-who has inflammation due to yeast-I think she clearly has a higher risk of getting a vaginal yeast infection than a woman who doesn't have that exposure. But there aren't many men like this, and I think overall it's pretty hard to show a real relationship.
ANNOUNCER: A more likely sexual cause of infection is receiving oral sex, though this is also relatively rare.
WILLIAM LEDGER, MD: I think the risk for a yeast infection following oral sex is related the person providing the oral sex being colonized in the mouth with yeast organisms. I don't know whether saliva, changes the local immune response, but I think we've found that many of these people have contamination with the yeast, and that's the source of the infection.
ANNOUNCER: Other than these rare cases, yeast infections are not likely to be transmitted from partner to partner, though other infections can be contracted this way.
DONNA SHOUPE, MD: The number of sexual partners a woman has probably doesn't have any significant bearing on the number of yeast infections that she gets. It can have a big impact on the number of bacterial infections that she has, but in terms of yeast infections, there's really no clear link and it generally has no correlation.
ANNOUNCER: This means that women who have what seems to be a yeast infection after any kind of sexual activity should check with their doctor to make sure it's not something more serious.
DAVID ESCHENBACH, M.D: I think the only way you can really differentiate a yeast infection from one of the other infections that would be sexually transmitted would be to receive an examination from a physician or a health care provider. Other than that, the unfortunate thing is that the symptoms are so indistinguishable and so general that it's very difficult to say, this discharge represents a yeast infection and a certain other discharge represents a sexually transmitted infection.
ANNOUNCER: While sex itself is unlikely to transmit a yeast infection, there is speculation that certain forms of birth control may increase a woman's risk.
DONNA SHOUPE, MD: Oral contraceptives are a risk factor for yeast infections, especially the higher-dose pills. Women who are on a birth control pill may want to move down to the 20 micro g pills if they suffer from recurrent yeast infections.
DAVID ESCHENBACH, M.D: Again because oral contraceptives have an impact on glucose metabolism to some degree and they increase the amount of estrogen, there's a slight correlation between taking oral contraceptives and getting yeast infections. However, we don't really recommend for people who get one or even more yeast infections that they stop their oral contraceptives. Because it's usually not helpful and there's usually many other factors that allow people to get yeast infections, besides the oral contraceptive.
ANNOUNCER: Others argue that it's not birth control pills that are to blame, but rather the effects of unprotected sex on the woman's immune system.
WILLIAM LEDGER, MD: Since we've had the availability of oral contraceptives, what this has meant for most women is that they're exposed to the ejaculate. The ejaculate is a very, very potent immunosuppressing agent. And that's good for pregnancy, but it may not be good for local immune responses to fight off organisms that are there to keep things in order.
ANNOUNCER: Vaginal contraceptions like iud's and diaphragms may also contribute to a woman's risk
DONNA SHOUPE, MD: Certainly any mechanical device that's in the vagina does tend to increase the risk of all vaginitis and this actually includes yeast vaginitis. And those would be IUD, with the IUD string, or the use of diaphragms or the cervical caps. It changes the flora in the vagina and can change the type of bacteria or yeast that grow there.
ANNOUNCER: Regardless of the possible connection between contraception and yeast infections, it's clear that women who do have a yeast infection should be wary of sexual activity while they're treating their condition.
DONNA SHOUPE, MD: It's usually recommended not to have vaginal intercourse while you're on treatment. There is a big problem if you are trying to use a diaphragm or a condom-really more a condom than a diaphragm. For one, it's not comfortable and there's-if you're using a cream, it's certainly very messy, but even more important is some of the oils will interfere with the latex and actually degrade it and so it increases your risk of pregnancy.
DONNA SHOUPE, MD: Women certainly can have sex after using an oral treatment, but it's usually recommended that the infection be cured prior to sexual intercourse, but it's easier after oral rather than vaginal treatments.
ANNOUNCER: Of course, the most important thing for women to remember isn't that yeast infections are not usually caused by sex, but rather that many more serious conditions are. So keep yourself protected, and if you notice anything unusual, see your doctor right away.