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A delicate balance: the vaginal microbiome

A delicate balance: the vaginal microbiome

Many people are familiar with gut flora and microbiome - but the gut isn’t the only place that houses bacteria and other microbes in a delicate balance. The vagina also plays home to its own delicately balanced flora.

Lifestyle insight
Reading time: 3 minutes

The vaginal microbiome

The vaginal microbiome is a complex and constantly changing ecosystem which shifts in its composition continuously throughout both a woman’s menstrual cycle and throughout different stages of her life.1

The microbiome of the vagina is made up of billions of microbes.1 The microbial species that inhabit the vaginal tract play an important role in the maintenance of health, and reduction of bacterial imbalances.2

The vaginal microbiome is generally predominated by Lactobacillus species bacteria.1 The most common of which are L. iners, L. crispatus, L. gasseri, and in smaller amounts L. acidophilus, L. fermentum, L. plantarum,  L. casei, L. reuteri, and L. rhamnosus. 2

These particular bacteria thrive in the vaginal environment and produce antimicrobial compounds such as lactic acid, and hydrogen peroxide that help to keep the vagina healthy, and to work as a natural defence.1

Lactobacillus can also stick to the vaginal wall and stop other microbial cells from binding to the cell sites.1 However, the microbial balance in the vagina, like the gut, can be disrupted which can then lead to the overgrowth of undesirable bacteria.3


What can cause imbalances in your vaginal microbiome

The vaginal microbiome is sensitive and can be thrown off balance by many factors – some internal, and some external.


Internal factors that can affect the balance of vaginal flora include:

  • Hormone levels (especially oestrogen)
  • Age
  • Immune system1


Some of the external factors that may interfere with vaginal flora balance include:

  • Use of certain medications
  • Infection1
  • Sexual activity
  • Use of vaginal cleansing products4


Signs and symptoms that your vaginal flora may be out of balance

Vaginal flora imbalance can often be hard to spot, as it can be present without any symptoms. However, some of the common tell-tale signs that your vaginal flora may be out of balance include:

  • Change to normal vaginal discharge
  • Itching
  • Irritation
  • Vaginal odour
  • Increased vaginal pH2

Talk to your health professional if you notice anything unusual or out of the normal.


How to maintain a healthy vaginal microflora

The vagina is very good at self-cleaning and looking after itself, however, there are things we can do to support vaginal health and help maintain healthy vaginal microflora.

  • Avoid foods that feed the ‘bad’ bacteria such as refined sugar, yeasts, and fungus
  • Consider taking a probiotic supplement
  • Ensure that you include plenty of foods rich in prebiotics in your diet as these can help to promote the growth of ‘good’ bacteria – try things like leeks, onions, garlic, oats, bananas and soybeans5


Other important lifestyle habits to remember include:

  • Using mild, unscented soap to clean your genital area
  • Reducing stress
  • Staying well hydrated
  • Exercising regularly
  • Maintaining a healthy body weight
  • Wearing loose-fitting cotton underwear5


Did you know that your vaginal microbiome may affect your immune system?

Preliminary evidence suggests that the microbes that make up the vaginal microbiome may communicate directly with the immune system and affect the way it functions. When the balance of the vaginal microbiome is altered it could lead to changes in the immune response and inflammatory reactions. Changes in the vaginal microbiome could also have the opposite effect and lead to weakened immune responses and the a change in the balance of bacteria.6

To learn more about how probiotics can support your immune function read our article: How do probiotics boost immunity?


Which probiotic is best for vaginal health?

Taking specific probiotics orally has been found to maintain a healthy balance of vaginal flora.2

The main probiotics that appear to be beneficial are some from the Lactobacillus family – including Lactobacillus rhamnosus GR-1®, Lactobacillus reuteri RC-14®. You can find these particular strains of probiotics here: Femme Flora

A clinical trial of healthy women who took these particular probiotics found that it helped to increase the number of beneficial lactobacilli in their vaginal flora, helping them to maintain vaginal health.7

Always read the label and follow the directions for use.



1 - Chen X, et al. The Female Vaginal Microbiome in Health and Bacterial Vaginosis. Front Cell Infect Microbiol. 2020; 11: 631972.

2 - Cribby S, et al. Vaginal Microbiota and the Use of Probiotics. Interdiscip Perspect Infect Dis. 2008; 2008: 256490.

3 - Han Y, et al. Role of Vaginal Microbiota Dysbiosis in Gynecological Diseases and the Potential Interventions. Front. Microbiol. 2021; 12: 643422.

4 - Leyva-Gomez G, et al.  Modifications in Vaginal Microbiota and Their Influence on Drug Release: Challenges and Opportunities. Pharmaceutics. 2019; 11: 217.

5 - Huzien J. Can diet improve a person’s vaginal health? Medical News Today. https://www.medicalnewstoday.com/articles/327507 - Accessed 14-May-22

6 - Al-Nasiry S, et al. The Interplay Between Reproductive Tract Microbiota and Immunological System in Human Reproduction. Front Immunol. 2020. 16; 11: 378.

7 - Reid G, et al. Oral use of Lactobacillus rhamnosus GR-1 and L. fermentum RC-14 significantly alters vaginal flora: randomized, placebo-controlled trial in 64 healthy women. FEMS Immunology & Medical Microbiology. 2003; 35(2): 131-134


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