Vaginal pH is maintained by lactobacilli bacteria, which produce lactic acid. These bacteria are found naturally in the vagina and play an important role in keeping it healthy. They help to keep the balance of acids and bases in the vagina at a neutral level that prevents the growth of harmful bacteria and yeast. Lactobacillus species have been identified as having beneficial effects on the vaginal microbiome and are thought to be responsible for protecting against infections such as BV and UTIs. The main mechanism by which they do this is through producing lactic acid, which lowers the pH of the vagina to an acidic environment unfavorable for many pathogens.
Lactic acid production is essential for maintaining the optimal pH levels in the vagina, but other factors can also affect vaginal pH. For example, changes in hormones or menstrual cycles can alter the balance of bacteria in the vagina and lead to an increase in the number of bad bacteria or yeast. This can cause irritation, discharge, odor, and itching. Antibiotics can also upset the balance of bacteria in the vagina and make it more susceptible to infection. It's important to note that not all women have lactobacilli present in their vagina, and those who don't may benefit from probiotic supplements or other treatments to restore a healthy balance. Additionally, certain sexual practices can introduce new bacteria into the vagina and throw off its natural balance. These include unprotected sex, using condoms with spermicides, douching, and wearing tight clothing.
In conclusion, understanding how vaginal pH is maintained by lactobacilli bacteria and the role of lactic acid is crucial for keeping the vagina healthy. While there are many factors that can influence vaginal pH, such as age, lifestyle, and medications, making informed decisions about hygiene habits and diet can help keep the microbiome balanced. Women should talk to their doctor if they experience any unusual symptoms related to vaginal health. By taking care of their body's natural defenses against harmful bacteria and yeast, they can maintain optimal health and reduce their risk of developing infections.