What Is a Yeast Infection?

A yeast infection, also known as candidiasis (pronounced: can-dih- dy -uh-sis), is the name for a common infection caused by a type of yeast-like fungus called Candida . Small numbers of Candida are always present in our bodies, but normally we have the right balance of bacteria and other factors to keep them from growing too much. Sometimes, though, these yeast-like fungi do grow too much, and this can cause an infection. These infections usually occur in warm, moist parts of the body, such as the mouth and moist areas of skin. When they cause an infection in the vagina, it is known as vulvovaginal candidiasis.

Candida can overgrow for many reasons. Stress , pregnancy , and illnesses that affect your immune system may allow yeast to multiply, as can certain medicines. These include some birth control pills and steroids. Or if you're taking antibiotics, such as for strep throat , the antibiotics can kill "good" bacteria that also live in the body and normally keep the growth of Candida in the vagina in check. Yeast also flourish if a girl's blood sugar is high. Girls who have diabetes that isn't controlled are at a higher risk for yeast infections.

Many girls find that yeast infections tend to show up right before they get their periods  because of the hormonal changes that come with the menstrual cycle. Clothes (especially underwear) that are too tight or are made of materials like nylon that trap heat and moisture might lead to yeast infections because yeast can thrive in this type of environment. And douching and using scented sanitary products can upset the balance in the vagina and make yeast infections more likely.

It's common for girls who are not sexually active to get yeast infections. Although yeast infections are not considered sexually transmitted diseases , they can occasionally be spread from one sexual partner to the other. This is quite rare, however, and the partner of someone who has a yeast infection does not automatically have to be treated.

Do I Need to See a Doctor?

Treating a yeast infection is simple, but it's important to visit your doctor for the right diagnosis. Your doctor might take a urine sample - to rule out a urinary tract infection , which can cause similar symptoms - and some discharge from your vagina to examine under a microscope.

If you do have a yeast infection, your doctor will probably prescribe a vaginal cream, pill, or suppository to cure it. When you get home, follow all the directions on the package carefully. A suppository will come with an applicator to help you place the medicine inside your vagina, where it can begin to work. All of these types of medication can clear up your symptoms in a couple of days and cure the infection within a week. It's important that you take the medicine for the whole time that your doctor prescribes. If you stop taking it too soon, the infection could come back.

The doctor may also prescribe a cream you can apply around the vagina to relieve itching. Some of these creams are available without a prescription in your local drugstore, but you shouldn't just buy a cream if you think you have a yeast infection. It's important to see a doctor for your diagnosis, because if you actually have another type of infection the problem could get worse if it is not properly treated. Also, over-the-counter medicine should not be used by anyone who is under 12 or pregnant.

Yeast infections can be annoying, especially if they happen regularly. To help avoid them, follow your doctor's advice, and on your next trip to the mall stock up on cotton underwear (they don't have to be boring!) and buy some jeans with a loose fit. Your body will thank you.