Bacterial vaginosis (BV) is the most common vaginal infection found in women of reproductive age, estimated to occur in up to 70% of women. Up to 30% of women ages 14 to 49 are affected, but rates vary between ethnic groups. Untreated BV increases the risk for health complications, especially in those who are pregnant and sexually active. Natural, holistic therapies can aid successful treatment and prevent the recurrence of BV. (2)
What is Bacterial Vaginosis?
BV is caused by a shift in vaginal flora from the normal predominance of Lactobacilli species of bacteria. It is usually caused by increased growth of anaerobic gram-negative bacteria, like Gardnerella vaginalis. Lactobacilli produce hydrogen peroxide, which creates an acidic environment within the vagina, preventing infection. Anaerobic bacteria produce large amounts of enzymes that break down vaginal peptides into amines, contributing to the malodorous nature of BV. (2, 3)
The link between sexual activity and BV is not completely clear. Still, BV is more common in people who are sexually active with multiple partners, in people whose sexual partner also has BV, and in people who do not use condoms. Other risk factors for BV include vaginal douching, cigarette smoking, and sharing sex toys. (4, 5)
BV reduces the vagina's natural defenses against infections and other pathogens that can gain access to the upper genital tract, increasing the risk for sexually transmitted infections (STIs) like HIV, herpes simplex virus, chlamydia, and gonorrhea. BV and STIs can also cause pelvic inflammatory disease (PID), an infection within the uterus, fallopian tubes, or ovaries. (2, 5)
Other complications are associated with untreated BV. BV in pregnant women is correlated to premature birth and low birth weight babies. BV also increases the risk of post-surgical infection after procedures like hysterectomy and dilation and curettage (D&C). (5)
Bacterial Vaginosis Signs & Symptoms
BV is diagnosed using the Amsel Criteria when at least three of the following clinical and microscopic findings are present:
- Homogeneous vaginal discharge
- Vaginal fluid pH greater than 4.5, caused by a reduction in hydrogen peroxide-producing Lactobacilli
- Positive "whiff test": an amine (fishy) odor observed when 10% potassium hydroxide solution is added to vaginal secretions
- Presence of clue cells (at least 20%) on wet mount microscopy: these cells appear fuzzy without sharp, delineated edges
The most common symptoms of BV are a thin vaginal discharge and a malodorous, "fishy" smell. The vaginal discharge typically has a gray-white color but can vary in color and volume. Patients may also report vaginal itching, pain with urination, and pain with sex. However, up to 84% of patients with BV will not have any symptoms and only discover they have it through a routine gynecologic exam. (1)
Causes of Bacterial Vaginosis
Vaginal dysbiosis, an imbalance in the "good" and "bad" bacteria in the vagina, is at the root of bacterial vaginosis. The three main factors responsible for the decline in Lactobacillus numbers include intercourse without condoms, douching, and broad-spectrum antibiotics.
Gut dysbiosis can also translate to vaginal dysbiosis. Given their close anatomic proximity, the origin of microorganisms colonizing the cervicovaginal space has been traced to the rectum. Dysbiosis originating in the gut can translocate to the vagina, altering vaginal Lactobacillus dominance.
Hormonal imbalances can also alter the composition of the vaginal microbiome. Estrogen promotes vaginal colonization by Lactobacilli, which metabolize glycogen and produce lactic acid, creating an acidic vaginal environment that prevents vaginal infections. Decreased estrogen levels, such as in the post-menopausal state, deplete Lactobacilli in the vagina and increases vaginal pH, predisposing the vagina to colonization by opportunistic bacteria. Hormonal imbalances can also cause frequent periods; the neutral pH of menstrual blood passing through the vaginal canal can cause vaginal pH to rise, increasing the risk of BV.
Functional Medicine Labs to Test for Root Cause of Bacterial Vaginosis
A vaginosis panel combines microscopic analysis and gram-staining of vaginal secretions to identify gram-negative bacteria and clue cells characteristic of BV. This panel also screens for vulvovaginal candidiasis and Trichomonas vaginalis, other common causes of vaginal symptoms that may occur alongside BV. Antimicrobial susceptibility testing to prescriptive and natural agents is performed for identified bacterial and fungal species to guide effective treatment recommendations.
Patients with recurrent BV infection can benefit from a more extensive microfloral evaluation of the vagina and gut with specialty vaginal and intestinal microbiome analyses. A lack of Lactobacillus and overgrowth of anaerobic bacteria (e.g., Gardnerella vaginalis, Mycoplasma hominis, and species of Mobiluncus, Bacteroides, Peptostreptococcus, Fusobacterium, Veillonella, Eubacterium, and Clostridium) is a characteristic microbial pattern in recurrent BV. (6)
Serum and urine tests can measure sex hormones (estrogen, progesterone, testosterone) and their metabolites to comprehensively evaluate possible hormonal imbalances contributing to irregular menstrual cycles and vaginal dysbiosis.
Doctors may also consider ordering a complete STI panel for patients at risk for STI exposure. Risk factors include being young (age 15-24), having multiple sex partners, having unprotected sex, and having sex while under the influence of drugs or alcohol.
Conventional Treatment for Bacterial Vaginosis
Treatment is recommended for all symptomatic women with antibiotic therapy. First-line treatment recommendations include an oral or topical course of metronidazole or clindamycin. All options are safe and comparably effective. Oral antibiotic therapy has been shown to reduce pregnancy-associated morbidity, whereas topical treatments have not. (1)
Functional Medicine Treatment for Bacterial Vaginosis
Therapeutic strategies behind treating bacterial vaginosis include: lowering vaginal pH, promoting immune response, restoring microfloral balance, reducing inflammation, and supporting antimicrobial activity.
Nutrition for Bacterial Vaginosis
A well-balanced, healthy diet rich in whole foods and low in fat, sugars, processed foods, and alcohol optimizes health, reduces inflammation, supports hormonal balance, and encourages microbiome homeostasis.
Diets high in refined carbohydrates and sugars can promote negative dysbiotic patterns within the intestinal and vaginal microbiomes. Limiting the intake of refined carbohydrates and sugars can prevent dysbiosis.
Dietary folate, vitamin A, and calcium intake may decrease the risk of severe BV. Good food sources of folate include a wide variety of fruits, vegetables, grains, and legumes. Vitamin A-rich foods include liver, fish, eggs, dairy products, and orange/yellow vegetables. Dairy products, bone-in fish, cruciferous vegetables, and tofu are high in calcium. (7)
Supplements for Bacterial Vaginosis
Oral and vaginal probiotics effectively support antimicrobial therapies to treat BV and prevent its recurrence. Strains of Lactobacillus, acidophilus, rhamnosus, fermentum, and reuteri are commonly administered to promote vaginal health. (8-10)
Vitamin C has beneficial effects on the immune system, and research has shown that vaginal administration of vitamin C can eradicate harmful bacteria, increase Lactobacillus growth, and lower vaginal pH.
Natural Antibiotics for Bacterial Vaginosis
Boric acid is safe and inexpensive and has been used for over one hundred years to treat vaginal infections, such as BV and candidiasis. A treatment rate of up to 100% has been reported for vulvovaginal candidiasis with boric acid. A recent 2021 study concluded that intravaginal boric acid used in addition to antibiotic therapy is an effective therapy in treating BV. A 2019 review reported similar findings in treating BV and vaginal yeast infections. (11-13)
Tea tree oil has been studied to treat trichomoniasis, candidiasis, and other vaginal infections. Given its potent broad-spectrum antimicrobial properties, diluted intravaginal tea tree preparations have been used to treat BV.
Goldenseal and Oregon Grape Root contain a compound called berberine, which acts as an antibiotic and immune enhancer. Research has shown that berberine therapy for BV results in decreased vaginal inflammation and improved clinical symptoms.
Prevention for Bacterial Vaginosis
Promote a healthy vaginal microbiome by avoiding vaginal douching, which changes the natural balance of bacteria, and avoiding vaginal contact with anything that has touched the anus (e.g., toilet paper, fingers, sex toys) (14).
Cotton wicks away moisture. Cotton or cotton-lined underwear creates a dryer vulvovaginal environment and prevents bacterial overgrowth. (14)
Minimize vaginal irritation by using unscented soaps, tampons, and pads (5).
Use condoms when engaging in sexual activity and wash sex toys after every use (5).
Bacterial vaginosis is a common vaginal infection caused by a shift in the healthy vaginal flora. Although not considered an STI, BV is more common in sexually active individuals. Antibiotic therapy is the conventional treatment recommendation for all symptomatic people. For some, BV can recur after treatment. Specialty testing can identify chronic imbalances in the vaginal and intestinal microbiomes and hormonal fluctuations that can predispose to recurrent BV. Lifestyle habits promoting good vaginal hygiene, dietary choices, and natural supplements establish a healthy vaginal microbiome and prevent BV recurrence.
Lab Tests in This Article
1. Majeroni, B. A. (1998). Bacterial vaginosis: an update. American Family Physician, 57(6), 1285–1289, 1291.
2. Kairys, N., & Garg, M. (2022). Megaloblastic Anemia. StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK459216/
3. Coleman, J.S., & Gaydos, C.A. (2018). Molecular Diagnosis of Bacterial Vaginosis: an Update. Journal of Clinical Microbiology, 56(9). https://doi.org/10.1128/jcm.00342-18
4. Sobel, J. (2022, September 14). Patient education: Bacterial vaginosis (Beyond the Basics). UpToDate. https://www.uptodate.com/contents/bacterial-vaginosis-beyond-the-basics/
5. Bacterial vaginosis - Symptoms and causes. (2021, July 21). Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/bacterial-vaginosis/symptoms-causes/syc-20352279
6. Girerd, P. H., MD. Bacterial Vaginosis: Practice Essentials, Background, Pathophysiology. https://emedicine.medscape.com/article/254342-overview
7. Neggers, Y.H., Nansel, T.R., Andrews, W.W., et al. (2007). Dietary Intake of Selected Nutrients Affects Bacterial Vaginosis in Women. Journal of Nutrition, 137(9), 2128–2133. https://doi.org/10.1093/jn/137.9.2128
8. Ya, W., Reifer, C., & Miller, L.E. (2010). Efficacy of vaginal probiotic capsules for recurrent bacterial vaginosis: a double-blind, randomized, placebo-controlled study. American Journal of Obstetrics and Gynecology, 203(2), 120.e1-120.e6. https://doi.org/10.1016/j.ajog.2010.05.023
9. Webb, L. J. (2021). Probiotics for preventing recurrent bacterial vaginosis. JAAPA, 34(2), 19–22. https://doi.org/10.1097/01.jaa.0000731484.81301.58
10. Martinez, R.C.R., Franceschini, S.A., Patta, M.C., et al. (2009). Improved cure of bacterial vaginosis with single dose of tinidazole (2 g),Lactobacillus rhamnosusGR-1, andLactobacillus reuteriRC-14: a randomized, double-blind, placebo-controlled trial. Canadian Journal of Microbiology, 55(2), 133–138. https://doi.org/10.1139/w08-102
11. Mullins, M.M.Z., & Trouton, K. (2015). BASIC study: is intravaginal boric acid non-inferior to metronidazole in symptomatic bacterial vaginosis? Study protocol for a randomized controlled trial. Trials. https://doi.org/10.1186/s13063-015-0852-5
12. Powell, A., Ghanem, K.G., Rogers, L., et al. (2019). Clinicians' Use of Intravaginal Boric Acid Maintenance Therapy for Recurrent Vulvovaginal Candidiasis and Bacterial Vaginosis. Sexually Transmitted Diseases, 46(12), 810–812. https://doi.org/10.1097/olq.0000000000001063
13. Surapaneni, S., Akins, R.E., & Sobel, J.D. (2021). Recurrent Bacterial Vaginosis: An Unmet Therapeutic Challenge. Experience With a Combination Pharmacotherapy Long-Term Suppressive Regimen. Sexually Transmitted Diseases, 48(10), 761–765. https://doi.org/10.1097/olq.0000000000001420
14. Bacterial Vaginosis (BV): Causes, Symptoms & Treatment. Cleveland Clinic. https://my.clevelandclinic.org/health/diseases/3963-bacterial-vaginosis#prevention