There is a delicate balance between various microbes and human cells in the vagina at all times. The delicate balance of these can be disturbed by antibiotics & medications, aging, sexual activities, and more. When changes do occur in the vaginal microbiome there is the possibility of increased risk of contracting sexually transmitted infections (STIs) and during pregnancy the risk of inducing pre-term birth through PPROM. Thus, it is important to make sure we maintain a healthy composition of our vaginal microbiomes, especially when it can impact the immune system of your baby long after it is born.
To start, a healthy adult vaginal microbiome is typically dominated by a bacteria known as Lactobacillus, which produces lactic acid and bacteriocin to maintain a low vaginal pH of 4.5 or less. The environment created by this helpful bacteria protects the vaginal microbiome from other harmful bacteria and yeast from growing.
Infant: vaginal microbiomes contains maternal estrogen to support the growth of Lactobacillus, but wanes by the fourth week of life.
Early childhood (1 – 8 years): vaginal pH is either neutral or basic (high pH), as its microbiome consists mostly of microbes found in our gut and skin.
Puberty (8 – 13 years): the hormonal and human cells change, which begins the process of increasing good bacteria that produce lactic acid, like Lactobacillus.
Reproductive years: the menstrual cycle of a woman controls hormonal changes and increases in estrogen allow for dominance of Lactobacillus. During periods of low estrogen, the microbiome will once again change and be more susceptible to infections.
Pregnancy: disruption in the menstrual cycle that brings about stability to Lactobacillus dominance and maintained levels of estrogen.
Menopause: With the end of menstrual cycling there is a distinct reduction in estrogen, causing vaginal dryness with an increase in vaginal pH and lower levels of Lactobacillus.
The main concern for vaginal health is vaginal dysbiosis, where there is an imbalance in the microbe populations within the vagina. This can cause a number of health problems, such as the common bacterial vaginosis (BV) which impacts around 1 in 3 women in their lifetime. BV is causes thin vaginal discharge with a fishy odor.
BV is caused by a shift from a Lactobacillus dominant microbiome to a mixed community dominated by G. vaginalis and anaerobic bacteria. BV is often misdiagnosed for other conditions, such as yeast infections or STIs, such as chlamydia. Microbiome analysis can identify the microbe composition causing the problem to recommend the right treatment.
Importantly, with comprehensive microbiome analysis we report on what antimicrobial resistance genes are present informing what treatments to NOT use and which antimicrobials to USE. This can reduce the prevalence of recurrent BV and stop it completely for the individual.
Vaginal dysbiosis can also cause pre-term birth, which increases infant mortality and serious health problems drastically. There is a North American pre-term birth rate of 10.6% and 25 – 40% of these cases are due to microbiome related problems. This happens when certain types of bacteria populate the vaginal microbiome and degrade the mucous plug of the cervix and can compromise the uterus and amniotic sac. (Goldenberg, R. L., Hauth, J. C., & Andrews, W. W. (2000). Intrauterine infection and preterm delivery. New England journal of medicine, 342(20), 1500-1507.) Through comprehensive microbiome analysis we can identify the good bacteria that can prevent PPROM pre-term birth before it happens.
During menopause, vaginal dryness occurs with a decrease in helpful microbes that protect secretion generation. This decrease in helpful microbes, increases the likelihood of urinary tract infections and vaginal yeast infections. Post-menopausal women can develop a common condition atrophic vaginitis, which is a problem driven by vaginal microbiome changes.