Bacterial Vaginosis (BV) is a common vaginal condition affecting millions globally, resulting from an imbalance in the natural bacteria present in the vagina. This article explores the scientific understanding of BV’s potential link to cancer, its other health implications, and management strategies.
What is Bacterial Vaginosis?
Bacterial vaginosis occurs when the normal balance of bacteria in the vagina is disrupted. Normally, “good” bacteria, primarily lactobacilli, outnumber “bad” anaerobic bacteria. An overgrowth of these anaerobic bacteria leads to BV. While the precise cause is not fully understood, certain factors can increase the risk.
Common symptoms include unusual vaginal discharge that may be thin, gray, white, or greenish. A foul-smelling, “fishy” vaginal odor, especially after sex, is also characteristic. Some individuals may experience vaginal itching or irritation, or a burning sensation during urination. However, up to 84% of people with BV may not experience any symptoms.
Does BV Directly Cause Cancer?
Current scientific consensus indicates that Bacterial Vaginosis itself does not directly cause cancer. However, research has explored indirect associations or increased risks of certain conditions that might influence cancer development. This indirect relationship is primarily observed in the interaction between BV and Human Papillomavirus (HPV), a known cause of cervical cancer.
Chronic inflammation and changes in the vaginal microbiome due to BV may influence the persistence or progression of HPV infections. When there are fewer lactobacilli, the vagina’s protective mucosa can be disrupted, potentially allowing HPV to access basal cells more readily. Studies have shown that HPV infections tend to persist in cases of vaginosis, which can lead to the appearance of epithelial lesions. High levels of certain bacteria common in BV, such as Gardnerella, A. vaginae, and Sneathia species, have been observed more frequently in women with persistent high-risk HPV infections.
The decrease in lactic acid and hydrogen peroxide, produced by lactobacilli, due to an increase in anaerobic bacteria can affect the protective ability of the mucosal epithelial barrier. This altered microenvironment, along with the production of pro-inflammatory cytokines, may increase the likelihood of persistent HPV infection, which can contribute to cervical cancer development.
Other Health Implications of BV
BV has significant health concerns and potential complications if left untreated or if it recurs. It increases susceptibility to sexually transmitted infections (STIs), such as HIV, herpes simplex virus, chlamydia, and gonorrhea. If an individual with HIV also has BV, there is a higher risk of transmitting the virus to a partner.
Bacterial vaginosis can also lead to pelvic inflammatory disease (PID), an infection of the female reproductive organs including the uterus, fallopian tubes, and ovaries. Untreated PID can result in severe complications, such as scar tissue formation in the fallopian tubes, which may cause chronic pelvic pain and increase the risk of infertility. Additionally, PID can lead to ectopic pregnancies, where a fertilized egg grows outside the uterus, a life-threatening condition.
For pregnant individuals, BV carries specific risks, including an increased likelihood of preterm birth or having a baby with low birth weight. While some studies suggest these risks may be linked to other factors like a history of early delivery, healthcare providers generally recommend testing and treatment for BV during pregnancy if symptoms are present. BV may also increase the risk of infection after gynecological surgeries like hysterectomy or dilation and curettage.
Addressing and Preventing BV
Diagnosis of bacterial vaginosis typically involves a medical history review, a pelvic exam, and laboratory tests. During a pelvic exam, a healthcare provider will visually inspect the vagina and may take a sample of vaginal discharge. This sample can be examined for “clue cells,” which are vaginal cells covered in bacteria and are a sign of BV. The acidity of vaginal fluid can also be tested using a pH strip, with a pH of 4.5 or higher often indicating BV.
Treatment for BV usually involves antibiotics, which can be prescribed as oral pills or as a topical gel or cream inserted into the vagina. Common medications include metronidazole, clindamycin, tinidazole, and secnidazole. It is important to complete the entire course of antibiotics, even if symptoms improve, to prevent the infection from returning. Individuals using certain vaginal creams or suppositories should be aware that these may weaken latex condoms, requiring alternative birth control methods during treatment.
Preventive measures focus on maintaining a healthy vaginal environment. Avoiding douching is recommended, as it can disrupt the natural balance of bacteria in the vagina. Using only warm water or mild, unscented soap for genital hygiene is advised, as scented products can irritate vaginal tissues. Practicing safe sex by using condoms or dental dams can also help reduce the risk of BV, especially with new or multiple sexual partners. Regularly cleaning sex toys after each use is also a beneficial practice.