Bacterial Vaginosis During Pregnancy

Bacterial vaginosis during pregnancyApproximately 10% – 30% of pregnant women will experience Bacterial vaginosis (BV) during their pregnancy. Bacterial vaginosis is caused by an imbalance in the normal bacteria that exists in a woman’s vagina. It is not transmitted sexually, but is associated with having vaginal intercourse. You may or may not experience symptoms.

How do I know if I have bacterial vaginosis?

One of the symptoms of BV is a gray or whitish discharge that has a foul fishy odor. However some women do not experience any symptoms.  Diagnosis is made through a pelvic exam. Vaginal discharge is tested through a wet mount (microscopic slide test), pH test (BV often causes a pH level of 4.5 or higher), KOH slide (microscopic slide test) or a whiff test (a mixture that causes a strong fishy odor).

What causes bacterial vaginosis?

Bacterial vaginosis is an imbalance of bacteria which leads to an over growth of bacterial species. The cause has not clearly been identified.  It is not transmitted sexually, but it is associated with having vaginal sex. Therefore, it may be listed under sexually transmitted diseases when you look it up.

How can bacterial vaginosis affect my pregnancy?

There is significant evidence that links bacterial vaginosis with preterm labor. Many recent studies have been conducted to verify this information and to find a method of prevention.  Other studies have also shown a possible link to miscarriages, low birth weight, and premature rupture of membranes.

If I am pregnant, will I be screened for bacterial vaginosis?

It is not necessary to screen non-symptomatic pregnant women for BV. When obtaining your prenatal care, bacterial vaginosis is not routinely screened. It is important that you discuss any concerns you may have about BV with your health care provider.

Why am I being screened for bacterial vaginosis?

The U.S Centers for Disease Control and Prevention (CDC) advises that all pregnant women with symptoms of bacterial vaginosis be screened and treated. The CDC also supports screening women who have had a previous preterm labor. Screening for BV is left up to your healthcare provider to decide.

What treatments are available for pregnant women with bacterial vaginosis?

Treatment is highly recommended to avoid any chance of preterm labor.  There are various treatments which include:

  • Oral medications – Clindamycin 300 mg or Metronidazole 500 mg twice daily for 7 days
  • Topical medications – Clindamycin 5 g or Metronidazole at bedtime for 5 days (This treatment may give symptomatic relief, but it is insufficient in preventing pregnancy complications.)

Research done in 2004 by McDonald H, Brococklehurst P and Parsons J, suggests that antibiotic treatment may reduce the risk of premature rupture of membranes and low birth weight for women with a history of preterm labor and who have BV. This study did not find any significant evidence that treatment reduces premature labor.

Last Updated: 05/2014