Bacterial Vaginosis

...chemical imbalance

According to the Centers for Disease Control and Prevention (CDC), bacterial vaginosis (BV) is the most common cause of vaginitis symptoms among women of childbearing age. It previously was called nonspecific vaginitis, or Gardnerella-associated vaginitis. Health experts are not sure what role sexual activity plays in developing BV.

Cause

BV is a sign of a change in the growth of vaginal bacteria. The resulting chemical imbalance occurs when different types of bacteria outnumber the normal “good,” or beneficial, ones. Instead of Lactobacillus (a type bacteria that normally lives in the vagina) being most common, increased numbers of bacteria such as Gardnerella vaginalis, Bacteroides, Mobiluncus, and Mycoplasma hominis inhabit the vaginas of women with BV.

Transmission

Although health experts are not sure what role sexual activity plays in developing BV, a change in sexual partners or having multiple sexual partners may increase a woman’s chances of getting the infection. Using an IUD (intrauterine device) and douching also may increase her risk of getting BV.

Symptoms

The main symptom of BV is an abnormal, foul-smelling vaginal discharge. Some women describe it as a fish-like odor that is most noticeable after having sex.

Other symptoms may include

1. Thin vaginal discharge, usually white or gray in color
2. Pain during urination
3. Itching around the vagina

Some women who have signs of BV, such as increased levels of certain harmful bacteria, have no symptoms. A health care provider who sees these signs during a physical examination can confirm the diagnosis by doing lab tests of vaginal fluid.

Diagnosis

A health care provider can examine a sample of vaginal fluid under a microscope, either stained or in special lighting, to look for bacteria associated with BV. Then, they can diagnose BV based on

1. Absence of lactobacilli
2. Presence of numerous "clue cells" (cells from the vaginal lining that are coated with BV germs)
3. Fishy odor
4. Change from normal vaginal fluid

Treatment

Health care providers use antibiotics such as metronidazole or clindamycin to treat women with BV. Generally, male sex partners will not be treated. For updated information about the treatment for BV and other sexually transmitted infections, read the Centers for Disease Control and Prevention Sexually Transmitted Diseases Treatment Guidelines.

Complications

In most cases, BV causes no complications. There have been documented risks of BV, however, such as an association between BV and pelvic inflammatory disease (PID). PID is a serious disease in women that can cause infertility and tubal (ectopic) pregnancy.

BV also can cause other problems such as premature delivery and low-birth-weight babies. Therefore, some health experts recommend that all pregnant women who previously have delivered a premature baby be checked for BV, whether or not they have symptoms. A pregnant woman who has not delivered a premature baby should be treated if she has symptoms and laboratory evidence of BV.

BV also is associated with increased chances of getting one or more STIs, including chlamydia, gonorrhea, or HIV infection.