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Vaginitis and Vaginosis

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Also known as: Bacterial Vaginosis; Vaginal Infection; Yeast Infection; Candidiasis; Trichomoniasis; Trich; Vulvovaginitis

What are vaginitis and vaginosis?

Vaginosis is an infection of the vagina. Vaginitis is an inflammation of the vagina that may be due to vaginosis or other factors such as an allergy, irritant, or a decrease in the female hormone estrogen. Vaginitis is a very common condition, most frequently affecting women of child-bearing age. It has been reported by the Centers for Disease Control and Prevention (CDC) to affect over 21 million women between the ages of 14 to 49 years. The condition can cause genital itching and burning and sometimes an abnormal vaginal discharge. When the external genitalia (vulva) are also inflamed, the condition may be referred to as vulvovaginitis. The most common terms used by the general public for vaginitis/vaginosis are "yeast infection" and "vaginal infection."

Thumbnail diagram of the cervix

The vagina normally maintains a dynamic balance of normal flora – a mixture of "good" microorganisms that help protect the vagina, maintain its moderately acidic environment, and discourage the growth of disease-causing microorganisms. Lactobacilli are the most frequently encountered normal flora bacteria. A mixture of other microorganisms, such as corynebacteria, and some yeast may also be found.

A small amount of daily vaginal discharge is normal. This is usually clear or milky and varies in consistency and quantity during a woman's menstrual cycle.

Anything that disrupts the balance of normal flora and/or that irritates the tissues of the vagina or vulva can potentially cause vaginitis.

The most frequent causes of vaginitis/vaginosis (up to 90%) are infections due to:

  • Bacterial vaginosis, caused by a complex change in vaginal flora with a decrease in the number of normal lactobacilli and an increase in other bacteria, including Gardnerella vaginalis and Mycoplasma hominis.
  • Candida albicans (yeast) infection, also called candidiasis, and sometimes caused by other Candida species
  • Trichomonas vaginalis infection, also called trichomoniasis or "Trich," is a sexually transmitted parasitic infection.

Some other causes of vaginitis include:

  • Allergic and irritant reactions to feminine hygiene products, use of petroleum jelly products intravaginally, bubble baths, tight underclothing, synthetic fabrics that hold in moisture, perfumes, deodorant soaps, use of fabric softener sheets, latex condoms, etc.
  • Thinning of the skin in the vagina and a loss of lubrication that is due to decreased estrogen; this is called atrophic vaginitis and is primarily seen in women during and after menopause.
  • Hormonal imbalances
  • Rarely, a foreign body in the vagina (such as a small piece of toilet tissue in a child or a forgotten tampon in a menstruating woman); this can irritate and cause an infection.

Bacterial vaginosis can make a woman more vulnerable to other infections, specifically sexually transmitted diseases (STDs). STDs other than a trichomonas infection that can sometimes cause vaginitis/vaginosis include:

Vaginitis and vaginosis may occur at any age but are most common in women of child-bearing age who are sexually active, though it is important to note that many causes can also occur in those who are celibate and/or have never had sex. A woman may have more than one cause of vaginitis/vaginosis at a time.

Risk factors for vaginitis/vaginosis include:

  • Antibiotic use (can cause a loss of "good" bacteria)
  • Pregnancy (causes hormonal changes that may lead to irritation of the vagina)
  • Frequent douching (can cause irritation and/or loss of normal flora)
  • Multiple sex partners and/or a new sex partner
  • Intrauterine device (IUD) use
  • Oral contraceptives
  • Underlying diseases, such as poorly controlled diabetes, skin diseases (dermatitis), and other conditions that affect the immune system
  • Poor hygiene, especially when using the toilet
  • Smoking

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