No, Lactobacillus species are not a sexually transmitted disease (STD). Instead, Lactobacillus refers to a group of beneficial bacteria that naturally reside in various parts of the human body, including the female reproductive tract. These bacteria play an important role in maintaining health and protecting against harmful pathogens.
The Role of Lactobacillus in Your Body
Lactobacillus is a dominant bacterium in the vaginal microbiome. This “good” bacteria contributes significantly to a healthy vaginal environment. Its presence is a marker of vaginal health, with a healthy vagina typically dominated by species like L. crispatus, L. gasseri, and L. jensenii.
These bacteria perform several protective functions. They produce lactic acid, maintaining an acidic vaginal pH (typically 3.8-4.5). This acidic environment is crucial as it inhibits the growth of many undesirable bacteria and other microorganisms that could cause infections. Certain Lactobacillus strains also produce hydrogen peroxide and other antimicrobial substances that directly combat pathogenic organisms. Lactobacillus species adhere to the vaginal lining, creating a physical barrier and competing with harmful microbes for nutrients and attachment sites, preventing their colonization.
Distinguishing Lactobacillus from Sexually Transmitted Infections
A sexually transmitted infection (STI), also known as a sexually transmitted disease (STD), is caused by specific pathogens like bacteria, viruses, or parasites. These infections are primarily transmitted through sexual contact, including vaginal, oral, or anal sex. Examples of STIs include chlamydia, gonorrhea, herpes, HIV, and syphilis.
In contrast, Lactobacillus is a naturally occurring component of the human microbiome and is not a pathogen transmitted through sexual activity. Its presence in the vagina is normal and indicative of a healthy microbial balance. Lactobacillus is not an infection acquired through sex and does not cause the conditions typically associated with STIs, such as sores, unusual discharge, or systemic symptoms of an infection.
The fundamental difference is that STIs are foreign invaders that cause disease upon transmission, whereas Lactobacillus are resident microorganisms that actively protect the body. Detecting Lactobacillus in a vaginal sample is a sign of health, unlike detecting an STI pathogen, which signifies an infection requiring treatment. Maintaining a robust Lactobacillus-dominated vaginal microbiome can offer some protection against certain STIs by creating an unfavorable environment for pathogens.
What Happens When Lactobacillus Levels Are Imbalanced
While Lactobacillus is generally beneficial, an imbalance in its levels can lead to specific vaginal conditions, which are distinct from STIs. One common condition is Bacterial Vaginosis (BV), characterized by a decrease in protective Lactobacillus species and an overgrowth of other anaerobic bacteria. This shift disrupts the vaginal ecosystem, leading to symptoms like unusual discharge and odor. BV is a dysbiosis of the natural flora and is not an STI, although it can be associated with sexual activity and increase susceptibility to STIs.
Another condition, less commonly recognized, is Cytolytic Vaginosis (CV), sometimes called Lactobacillus overgrowth syndrome. This occurs when an excessive amount of Lactobacillus leads to an overly acidic environment that can irritate the vaginal lining. Symptoms of CV can include itching, burning, and discharge, which may be confused with yeast infections or BV. CV symptoms often worsen just before menstruation because of higher Lactobacillus levels during that part of the cycle. Both BV and CV are imbalances of the existing vaginal flora, not infections acquired through sexual transmission.
Tips for Maintaining Vaginal Health
Supporting a healthy vaginal microbiome primarily involves practices that encourage the natural balance of Lactobacillus. Proper hygiene is important, focusing on washing the vulva (external area) with plain water or a mild, unfragranced soap, while avoiding washing inside the vagina, as it is self-cleaning. Douching is generally discouraged because it can disrupt the delicate balance of beneficial bacteria, potentially leading to imbalances.
Wearing breathable underwear, such as cotton, and avoiding tight clothing can help maintain a dry environment less conducive to the growth of undesirable microorganisms. Some dietary choices, like consuming fermented foods containing live and active cultures such as yogurt, may help support the beneficial Lactobacillus population. Overall general health habits, including a balanced diet and managing stress, also contribute to a robust immune system and a healthy vaginal environment.