Vaginal yeast infection is a fungal infection of the vagina, most commonly due to the yeast known as Candida albicans. Candida albicans is a microorganism that is normally present on the skin and vagina and contributes to the normal "flora" of microorganisms that help keep us healthy. Infection occurs when the number of yeast organisms increases to a level that unbalances the normal flora, says MedlinePlus. Almost all women will experience at least one yeast infection in their lifetimes, but about 5 percent of women are plagued by frequent, recurrent infection.
Vaginal pH
The vagina is normally an acidic environment, and it is this acidity that naturally helps this area of a woman's body remain healthy. When the vagina becomes more basic, harmful microorganisms grow more efficiently while beneficial flora decrease. Vaginal pH can change due to use of intrauterine devices, feminine hygiene products, birth control pills and tampons. The pH can also be unbalanced by menstruation or the presence of semen. Eating yogurt with live Lactobacillus acidophilus cultures or taking Lactobacillus tablets can be beneficial to re-balancing proper pH.
Antibiotics
Antibiotics can destroy the normal vaginal flora, alter the pH and allow the overgrowth of yeast. Eating live Lactobacillus cultures while on antibiotics can help counteract these changes.
Weak Immunity
Women with recurrent vaginal infections may have an underlying disease that is weakening their immunity. If recurrent yeast infections return immediately after treatment or do not respond to treatment at all, women may want to be tested for HIV, according to the National Institutes of Health.
Diabetes and Pregnancy
According to the American Diabetics Association, increased circulating blood sugar provides food for yeast organisms and can lead to a higher frequency of yeast infections in diabetics. Keeping the blood sugar levels under control may help manage infections.
Pregnancy increases levels of circulating estrogen, and this hormonal shift can promote the overgrowth of yeast. Some women also develop diabetes during pregnancy.
Moisture
Excess moisture can make a more hospitable environment for yeast. Some women use a blow dryer after showering to help decrease moisture. You should also wear dry, loose-fitting undergarments for good air circulation.
Bacteria
Yeast and other harmful bacteria that can make your vagina more hospitable to a yeast infection are present around the rectum. Women should always cleanse in a front-to-back manner after using the toilet to avoid transporting microorganisms to the vagina.
