- What is Bacterial Vaginosis?
- What are the signs of BV?
- What increases my risk for BV?
- How is BV diagnosed?
- Does BV always require treatment?
- Treatment of Recurrent or Frequent BV
- Natural or Home Remedies for BV
- Why Does BV Recur and What is a Biofilm?
- Should my sexual partner be treated?
- Can I be safely treated if I am pregnant?
- Why should BV be treated during pregnancy?
- How Can I Prevent BV?
- About 21.2 million new bacterial vaginosis (BV) cases occur yearly.
- BV is not a sexually transmitted disease (STD) but has been linked to sexual activity.
- BV increases your risk for sexually transmitted infections.
- You should get treated for BV during pregnancy. If you don’t, it could increase your risk of pregnancy complications.
What is Bacterial Vaginosis?
According to the Centers for Disease Control and Prevention (CDC), BV is the most common vaginal condition in women aged 15–44. The CDC estimates that 21.2 million new BV cases occur annually in the United States among women in this age group.
BV is the most common cause of a fishy-smelling abnormal vaginal discharge; it accounts for more than half of vaginitis cases, yet up to 84% percent of women infected with BV show no symptoms.
Here are some facts you should know about BV:
- Women who have never been sexually active account for less than 18% of cases of BV.
- Pregnant women account for 25% of BV cases.
- It is not fully understood how the changes in the microorganisms that usually inhabit the vagina (known as the vaginal microbiome) cause BV.
- It is not clear if BV results from a single sexually transmitted pathogen.
- BV is not considered an STD but has been linked to sexual activity.
- The prevalence of BV infections is related to the number of lifetime sexual partners.
- Hormonal contraception does not increase your risk for BV, while using copper-containing IUDs does.
What are the signs of BV?
Bacterial vaginosis is associated with a thick white vaginal discharge with a fishy odor.
BV will cause you to lose some of your normal, healthy, vaginal Lactobacillus bacteria, allowing pathogenic (infection-causing) microbes to take over.
The primary infectious agent that causes BV is Gardnerella vaginalis. However, there are other BV-associated microbes.
In addition to a fishy, thin, white discharge, BV can cause:
- irritation of the genital area
- stinging, burning, itching, or swelling
- pain with urination
- pain with intercourse (dyspareunia)
What increases my risk for BV?
- Sex with a new partner
- Sex with multiple partners (male and female)
- Having many different partners over your lifetime
- Not using a condom
- Having a copper-containing IUD in place
- Having your menses
- Having herpes virus (HSV-2)
- An uncircumcised male partner
We also know that women with BV are at increased risk for:
- sexually transmitted infections (e.g., HIV, Gonorrhoeae, Chlamydia, Human Papillomavirus, and Herpes)
- complications after gynecologic surgery
- complications in pregnancy (e.g., premature birth and low birth weight babies)
- transmission of HIV to their male sex partners
- Pelvic Inflammatory Disease (PID)
- recurrences of BV
How is BV diagnosed?
- Your health provider will do a pelvic exam to examine your vagina and the vaginal discharge.
- A swab may be taken and sent to the lab, or a wet mount might be performed.
- Once a diagnosis of BV is made, your doctor will start your treatment.
Does BV always require treatment?
Doctors recommend treatment for non-pregnant women with symptoms to:
- relieve vaginal symptoms
- decrease abnormal vaginal discharge
- reduce the risk of acquiring a sexually transmitted infection
Currently, the CDC recommends treatment with one of the following:
- Metronidazole (Flagyl) pills
- Vaginal Metronidazole gel 0.75%
- Vaginal Clindamycin cream
- Alternative regimens are available for women who are allergic to these medications.
Here are some essential things to know about your treatment:
- Do not consume any alcohol during and for 24 hours after your therapy is complete. Drinking alcohol while taking metronidazole can cause severe nausea, vomiting, abdominal pain, flushing, fast heart rate, throbbing headaches, and fainting. In severe cases, it can affect your breathing and cause abnormal heart rhythms, convulsions, and even death.
- Clindamycin cream is oil-based and might weaken latex condoms and diaphragms for up to 5 days after use (refer to the clindamycin product labeling for additional information).
- Refrain from sexual activity or use condoms consistently and correctly during treatment.
- Do not douche. There is no data to support douching for treatment or relief of symptoms of any condition.
Once treatment is completed, a follow-up visit to your doctor is unnecessary, unless your symptoms recur.
Treatment of Recurrent or Frequent BV
First, your provider will do another test to be sure the recurrence is truly bacterial vaginosis and not some other type of vaginitis, such as yeast infection. Some providers repeat the first treatment regimen for a single recurrence, while others use a different one.
Unfortunately, 69% to 80% of women treated for BV will have a relapse or reinfection within 12 months.
Limited studies are available regarding the best way to treat persistent or recurrent BV.
Women who experience three or more episodes of symptomatic and confirmed BV in one year are classified as having recurrent BV. For women with recurrent BV, suppressive therapy is often prescribed.
Recurrent BV may be treated with suppressive (also called maintenance) therapy. Suppressive therapy involves using a drug not only for treatment but also for prevention of an infection.
Suppressive therapy for recurrent BV involves using the drug to treat the current inflammation. Once that treatment is complete, you will continue taking the drug, but less frequently.
For example, you may take vaginal metronidazole gel twice daily for seven days. After the seven days, you will continue taking metronidazole gel weekly for 4–6 months. Suppressive therapy will reduce recurrences. However, once the medication is stopped, BV can still recur.
Vaginal boric acid may be added to the treatment regimen if you continue to get BV while taking suppressive therapy. By itself, vaginal boric acid is not beneficial. One regimen involves inserting vaginal boric acid nightly for 30 days.
However, please be aware boric acid is a poison. Swallowing boric acid may be fatal. This drug must be kept away from children.
Oral intercourse must not occur while using boric acid. Boric acid must never be used in pregnancy.
Natural or Home Remedies for BV
Probiotics have garnered much public interest in the treatment of vaginitis. However, studies have shown mixed results and are not conclusive. More studies are needed before probiotics can be recommended for treating BV.
Many homemade therapies have been suggested for treating BV, including garlic, yogurt, and vaginal acidifying agents. Unfortunately, none of them have been proven effective. In fact, inserting non-therapeutic items into the vagina may further offset your vaginal flora, causing your symptoms to worsen.
Why Does BV Recur and What is a Biofilm?
A variety of bacterial and fungal microbes can form biofilms. When you wake up, the film that coats your teeth before you brush is an example of a biofilm.
In the case of BV, the microbe Gardnerella vaginalis establishes itself in the vagina and then creates a biofilm; it is like a scaffold to which other BV-associated microbes can attach.
The biofilm shelters G. vaginalis and other BV-associated microbes and keeps them protected from antibiotics, as well as from your immune system.
The biofilm also prevents the restoration of a healthy, balanced vaginal microbiome by preventing an increase in the normal vaginal microbes (Lactobacillus species). G. vaginalis and other BV-associated microbes can multiply, leading to a recurrence.
Should my sexual partner be treated?
Although BV-associated bacteria can be found in the male genitalia, data from clinical trials indicate that treating your male sexual partner has no effect on recurrence rates and is not recommended.
If your partner has a vagina, there is a 25-50% risk of transmission. Confirmed symptomatic cases of BV should be treated.
Can I be safely treated if I am pregnant?
Doctors recommend treatment with metronidazole pills or gel for all symptomatic pregnant women; it is safe in pregnancy, and both the pills and gel are equally effective, with cure rates of 70%.
Multiple studies have failed to demonstrate an association between metronidazole use during pregnancy and congenital disabilities.
Some older studies indicated that using vaginal clindamycin during pregnancy harmed the baby. Still, newer data demonstrate that this treatment approach is safe for pregnant women.
Your doctor may delay treatment until you have completed the first trimester of pregnancy.
Why should BV be treated during pregnancy?
If left untreated, symptomatic BV in pregnancy increases your risk for:
- premature rupture of membranes
- preterm labor
- preterm birth
- low birth weight
- uterine infections
Studies have looked at treating pregnant women with asymptomatic BV if they have a history of previous preterm delivery. The results are mixed, so routine screening for BV in asymptomatic pregnant women at high or low risk for preterm delivery is not recommended.
If BV is discovered during delivery, your provider may treat you with a single 2-g metronidazole dose to lower the intrauterine infection risk.
Metronidazole is secreted in breast milk, but the 2-g dose produces a low concentration and is considered safe for breastfeeding.
Multiple studies have failed to identify metronidazole-associated adverse effects for breastfed infants. However, some providers still recommend deferring breastfeeding 12–24 hours after treatment.
How Can I Prevent BV?
There are some things you can do to help lower your chances of getting BV:
- Maintain good personal hygiene.
- Avoid wearing tight jeans or spandex.
- Don’t douche or use vaginal sprays or scented soaps.
- Practice safe sex.
- Get screened for sexually transmitted infections.
- Have regular gynecologic exams to maintain vaginal health.
Bacterial Vaginosis is the most common cause of vaginitis. While this condition can cause discomfort and frustration, effective treatment is available.
Ensuring you have the correct diagnosis through testing is a critical first step. Treatment is important. Not only does treatment relieve you of symptoms, but it also restores the health of your vagina, thereby reducing your risk of acquiring more serious sexually transmitted infections.
Written by: Lisa Shephard, MD | Editor: Jennifer Abayowa and Dayna Smith, MD | Reviewed August 21, 2023 | Copyright myObMD, Inc, 2023
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