Maintaining the pH balance of the vagina is essential to keeping it healthy. A pH below 7 is acidic, while a pH above 7 is basic. A normal vaginal pH is usually less than 4.5. The lower the number, the more acidic the vaginal environment will be.
Doctors can take a vaginal pH measurement to determine how acidic the vaginal environment is. It is also possible to test this at home.
In the vagina, a high pH may cause infections as it can allow bacteria and yeast to thrive.
In this article, learn more about normal vaginal pH levels, how to test them at home, and what to do to restore vaginal pH balance.
A normal vaginal pH is between 3.8 and 4.5. A pH level within this range can help to keep bacterial and fungal infections at bay.
Lactobacilli bacteria live in the vagina and secrete lactic acid and hydrogen peroxide, which give the vagina its acidic pH level.
Vaginal pH is usually less than 4.5 during a woman's reproductive years unless a condition or infection raises it.
Several conditions and infections can affect the vaginal pH balance, usually by increasing pH levels.
Causes of changes in vaginal pH include the following:
Bacterial vaginosis is a medical condition that occurs when too much bacteria is present in the vagina. This can cause an increase in vaginal pH levels.
A person with bacterial vaginosis may experience itching, burning, or pain in the vagina. They may also feel a burning sensation when urinating and notice a white or gray discharge.
Douching refers to washing or cleaning the vagina using particular solutions, such as those containing vinegar or baking soda.
These solutions claim to reduce vaginal odor, but, in fact, they may worsen the smell. This is because they wash out good bacteria, which affects the vaginal pH balance and can make someone more prone to infections.
Reduced estrogen levels during menopause may affect a person's vaginal pH.
Other vaginal infections
The presence of infections other than bacterial vaginosis may also increase the vaginal pH.
Examples include Trichomonas vaginalis and group B Streptococcus (GBS).
Presence of menstrual blood
Blood has a higher pH than the vaginal environment. When a person is menstruating, the presence of menstrual blood can increase vaginal pH levels.
Presence of semen
Semen is basic, which is the opposite of the vagina's acidic environment. When semen enters the vagina, it may temporarily increase the pH.
People use antibiotics to kill harmful bacteria, but these medications can kill good bacteria as well. This will include bacteria in the vagina. If a person is taking antibiotics, their vaginal pH may be out of balance.
Urinary tract infections (UTIs)
UTIs do not cause a higher vaginal pH, but having a high pH can increase a person's risk of developing a UTI.
Reduced estrogen levels during perimenopause and menopause can put a person at risk of developing more frequent UTIs, as lower estrogen allows the vaginal pH to rise.
Doctors may prescribe estrogen treatments to lower the vaginal pH and to prevent further UTIs.
People can purchase home-testing kits that measure the pH balance of the vagina. These kits are available in some pharmacies and online.
At-home testing can reveal elevated pH levels, which could indicate the presence of an infection.
The test involves placing a strip of paper that measures pH against the wall of the vagina for a designated amount of time.
After removing the paper, a person can compare the resulting color to those on a chart in the kit. Each color corresponds to a pH value.
People should read all of the information that the test kit includes. This will include recommendations on the timing of the test, including not performing the test while menstruating or too soon after sex.
If a person's vaginal pH levels are routinely high without any symptoms of an infection, they can take several steps at home to reduce their pH levels. These include:
- Avoiding harsh soaps and douching. Soaps typically have a high pH, and using them to clean the vaginal area may increase vaginal pH. It is best to use warm water and a gentle cleanser to clean the vulva but to refrain from using soap inside the vagina. This will help to maintain the vaginal pH balance.
- Taking a probiotic supplement or suppository. Probiotics help to restore the body's natural bacterial levels. Some foods also contain probiotics, including yogurt, miso, and kombucha.
- Changing tampons regularly. Leaving a tampon in for too long can increase the vaginal pH because the pH of blood is slightly basic. Changing tampons frequently also reduces the risk of bacterial infections, including toxic shock syndrome (TSS).
- Using barrier protection during sex. Using barrier protection, such as condoms or dental dams, not only helps to prevent pregnancy and STIs but can prevent semen and other fluids from affecting pH levels in the vagina.
Doctors can also prescribe creams, such as estrogen cream, which may help to reduce the vagina's pH levels.
Keeping vaginal pH levels in balance can help to reduce infections and prevent complications.
Doctors rarely rely just on measurements of vaginal pH to diagnose medical conditions, such as yeast infections, or to determine whether or not someone is approaching menopause. However, vaginal pH tests can help to confirm a suspected diagnosis.
People can take steps, such as using probiotic supplements and not douching, to help keep their vaginal pH levels balanced.