A balanced vaginal microbiota is a crucial component of women’s health warranting particular attention in order to limit infections causing uncomfortable symptoms such as itching, irritation, etc…

What is the vaginal microbiota?

Discovered by German gynaecologist Albert Döderlein, the vaginal microbiota is dominated by lactic bacteria called Lactobacilli (95%). But it also contains numerous other microorganisms present in lower quantities.

Lactobacilli guarantee a healthy, balanced vaginal flora. They form a genuine defence system against infections, via the formation of a protective biofilm on the vaginal mucosa, preventing the proliferation of pathogenic microorganisms.

To achieve this, they employ several mechanisms:

  • Stimulation of immune system.

  • Competition with other microorganisms for nutrients and adhesion sites on the vaginal epithelium.

  • Maintenance of an acidic pH in the vagina via the production oflactic acid. 

  • Production of antimicrobial substances, such as bacteriocins and hydrogen peroxide, which are toxic for pathogenic microorganisms.


The composition of this complex and dynamic ecosystem, which is normally rich in Lactobacilli, varies under the influence of numerous endogenous parameters, such as age, puberty, menstrual cycles and pregnancies, as well as other exogenous factors, such as potential infections, sexual activity, medication or hygiene.

These factors weaken the stability of the vaginal microbiota and can cause dysbiosis: harmful bacteria develop to the detriment of Lactobacilli. As a result of the loss of the protection offered by Lactobacilli, women become vulnerable to vaginal and/or urinary infections.

What intimate infections can affect women?

Bacterial vaginosis (BV) is a very common vaginal infection that affects lots of women. This multi-microbial infection is characterised by the strong growth of anaerobic bacteria such as Gardnerella vaginalis.

Often without any symptoms – and hence overlooked – BV can progress and cause discomfort, with itching and an unpleasant-smelling vaginal discharge.

Thrush, or candidiasis, is a fungal infection, primarily caused by Candida albicans. This benign infection causes itching, burning and a heavier vaginal discharge, adversely affecting the quality of life of women.

Most urinary infections are cystitis. This is by far the most common infection. It is due to contamination of the bladder, by an intestinal bacteria called Escherichia coli in 80% of cases. This pathogen of the gut microbiota travels up the urinary tract and colonises it. A frequent urge to pass urine, pain, blood in the urine and cloudy urine with an unpleasant smell are the main symptoms.

These infections – whether vaginal or urinary – are a common reason for consulting a doctor and tend to be recurrent.

Specific case of pregnant women

Pregnant women are also prone to vaginal or urinary infections, which can have an impact on their pregnancies.

For example, an imbalance in the vaginal microbiota, accompanied by bacterial vaginosis can be a trigger for premature birth in pregnant women and perinatal complications. That is because there is an increased risk of premature labour and premature rupture of the foetal membranes.

How can probiotics relieve intimate problems in women?

Probiotics can act on the balance of the vaginal ecosystem and combat these infections.

They have been shown to be effective on the genital tract when taken orally: the vaginal microbiota “inherits” certain bacteria from the gut microbiota. This close relationship means that probiotics taken orally can help maintain and restore the balance of a vaginal flora rich in Lactobacilli.

In the event of infection, probiotics reinforce the body’s natural defences by improving the barrier effect of the intestinal mucosa: they limit the establishment and development of pathogenic microorganisms such as Candida albicans and Escherichia coli, liable to colonise the urinary tract from the gastrointestinal tract.

They also improve symptoms associated with bacterial vaginosis and urinary infections, reducing women’s intimate discomfort.
Used as a preventive treatment, probiotics limit the rate of recurrence.