Vaginal health - Avoiding Thrush & UTIs

Vaginal health - Avoiding Thrush & UTIs

I heard recently that 1 in 5 women visiting a pharmacist go there for issues related to vaginal health – with many women battling vaginal dysbiosis (sometimes known as thrush) or urinary tract infections - often repeat occurrences and particularly prevalent in post-menopausal women.

I was blown away by these statistics, so I tried to find some official statistics to back up the anecdotal data without much luck – it seems vaginal dysbiosis is something that affects many women, yet it is something we don’t talk about – let alone research!

To investigate further, we have put together some of the latest thinking in terms of the role of natural probiotics in vaginal health and in reversing vaginal dysbiosis as well as UTIs.

This is longer than our usual blog, as we believe one of the best ways of finding solutions is to seek understanding.  We have included the peer-reviewed scientific publications from which we have derived this information if you want to read more deeply.  Conversely, if something in this blog, doesn’t make sense, then please reach out and ask us, we may not know the answer ourselves, but we can try and find an answer if its available.

Please share this blog widely so we can talk about vaginal health and encourage research into finding the best long-term solutions.

Healthy vaginal state

In a healthy state, the vaginal microbiota is characterised by a low diversity of microbes with predominant (~95%) colonisation by the Lactobacillus genera of bacteria (read more).  Lactobacilli produce lactic acid, which is what keeps the pH balance of the vagina at a slightly acidic level and prevents the growth of yeast, detrimental bacteria and other pathogenic organisms, which prefer a more alkaline environment. 

Within the Lactobacillus genera, there are a number of species with different functions/affects, the ratio of which can change.  For example, Lactobacillus crispatus, the most common species in a healthy vagina, does not induce vaginal mucosal inflammation, and it is also associated with protection from pathogens.  Conversely, Lactobacillus iners is much more easily displaced from the vaginal mucosa and often co-occurs with dysbiosis-associated microbes and the inflammatory process (read more).

It has been shown that specific bacterial species are able to colonise both the gastrointestinal and reproductive tract of women, which suggests that the rectum is the origin of bacteria commonly colonising the vagina (read more).

Vaginal changes with age

Age and reproductive status influence the vaginal microbiome:

  • During early childhood through to pre-pubescence, the vaginal pH is neutral, or only slightly alkaline, with lower concentrations of Lactobacillus species;
  • During puberty, increasing levels of oestrogen increase the proportion of Lactobacillus species, reducing the pH;
  • When a female is pregnant, hormonal changes trigger shifts in the vaginal microbiome to become even more Lactobacillus dominant;
  • During perimenopause, menopause and beyond, a reduction in sex hormones, especially oestrogen, can lead to vaginal dryness and/or atrophy; the pH of the vagina increases (becomes less acidic) leading to an increased risk for post-menopausal women of dysbiosis and urinary tract infections; Note oestrogen is required for glycogen to accumulate in vaginal epithelial cells; Lactobacilli metabolise vaginal glycogen into lactic acid, resulting in a low vaginal pH that keeps many other urogenital micro-organisms at bay (read more).

Vaginal dysbiosis

In everyday life, there are a number of reasons for vaginal microbiome changes including: hormonal fluctuations, menstruation, stress levels, the gastrointestinal microbiota at the nearby rectum, bathing and products used for hygiene, sexual interactions, the use of contraceptives, antibiotics and other medicines. 

An overgrowth of detrimental microbes in the vagina can lead to vaginal infections – decreasing the growth of lactobacilli, but increasing the growth of anaerobic bacteria, for example:

  • Candidiasis (candidosis/thrush), caused usually by Candida albicans;
  • Bacterial vaginosis (BV), caused by excess anaerobic bacteria including Prevotella sp., Mobiluncus sp., Gardnerella vaginalis, Ureaplasma, Mycoplasma and other fastidious or uncultivated anaerobes;
  • Trichomoniasis is caused by (the protozoan) Trichomonas vaginalis (read more).

In addition, the displacement of Lactobacillus species, produces elevated vaginal pH (less acidic) and predisposes women to other serious diseases including: pelvic inflammatory disease, HIV-1 transmission, and infection by Trichomonas spp., Chlamydia trachomatis, and Neisseria gonorrhoeae.

Infections of the vaginal microbiota significantly affect the quality of life of millions of women globally. Antimicrobial therapy is often poorly effective, causes side effects, and does not prevent recurrences (read more).  Extensive use of antibiotics for vaginal, or other health issues can also result in resistant micro-organisms – putting patients at risk from pathogen overgrowth and chronic problems.

Urinary tract infections

We have concentrated on vaginal dysbiosis for much of this blog, but we also wanted to discuss a related topic, urinary tract infections (UTIs), which sometimes arise from vaginal dysbiosis. 

UTIs describe an infection in any part of the urinary system. The urinary system includes the kidneys, ureters, bladder and urethra. Most infections involve the lower urinary tract — the bladder and the urethra.

Women are at greater risk of developing a UTI than men, and women over the age of 65 have double the rate of urinary tract infections as seen in the overall female population (read more). If an infection is limited to the bladder, it can be painful, but serious health problems can result if a UTI spreads to the kidneys.

UTIs are among the most common bacterial infection found in the community and hospitals and are mostly caused by Escherichia coli bacteria.  UTIs are often treated with antibiotics, but of real concern is that the E. coli causing UTIs are increasingly becoming antibiotic resistant (read more).  Healthcare-associated UTIs are the most common form of healthcare-acquired infection.   

As uropathogens are increasingly becoming resistant to currently available antibiotics, there is an urgent need to explore alternative strategies for preventing and managing UTI.

Avoid vaginal "hygiene" products

The vagina has been referred to as a “self-cleaning oven” (an interesting analogy) because of its ability to maintain its cleanliness and health, independent of the use of soaps or human-made cleansers.  Despite this, the feminine hygiene market is a $1.1 billion dollar industry (data from 2018, not including sanitary products) and is expected to continue to grow. Vaginal hygiene products include washes, wipes, moisturisers and creams, and other products­­, which often have adverse effects on the vaginal microbiome (read more).

One study in Canada (1,435 women) found that 95% of participants reported using at least one vaginal hygiene product.  Participants who used any vaginal product had nearly three times higher odds of an adverse health condition, such as reported history of BV, yeast infection, urinary tract infection, or a sexually transmitted disease (read more).  

Probiotics for vaginal health

The cleansing action of cell turnover, mucus production, and local immune defences all play a role in maintaining balance, but it is the role of beneficial bacteria that have drawn recent scientific interest (read more). 

The theory is that if we can naturally restore the acidic environment of the vagina by allowing the growth of lactic acid bacteria (read more), then we will reduce dysbiosis and infection rates. 

However, a challenge is that pre- and pro-biotic solutions for vagina health often cannot be protected (patented) and because of that, scientific research is still under-represented for the size of the problem and potential impact of finding solutions.

Probiotic application

The exogenous application, or oral supplementation, of probiotics introduces bacterial species that can compete against offending pathogens or disease processes which can replenish low abundances of existing lactobacilli, allowing species to return endogenously.

Two probiotic delivery approaches can be used:

  1. Directly application into the vagina.
    • The advantage is that the lactobacilli are delivered to the problem area where their activity can target pathogens more quickly; a disadvantage is that this represents a drug treatment, according to regulatory authorities, and therefore scientific trials and commercialisation are prohibitive to researchers and many companies.
  2. Oral administration.
    • The oral route simulates the natural means by which pathogens transfer from the rectum to the vaginal area because of anatomical proximity - essentially, colonisation of beneficial bacteria occurs in the gut and are passed out via the rectum and transferred to the vagina; this is believed to induce microbial competition, reducing pathogen infection; the disadvantage of oral administration is that the time for this to occur is longer than direct administration into the vagina and the billion or so lactobacilli ingested have to compete with trillions of microbes in the gastrointestinal tract and then make their way to the vagina - the net result is that relatively few lactobacilli ingested reach the vagina although the treatment still causes an increase in total lactobacilli in the vagina (read more).

Oral supplementation with Lactobacillus rhamnosus and Lactobacillus fermentum has been shown to restore the healthy vaginal microbiome in up to 82% of women with previous vaginal dysbiosis, specifically an increase in Lactobacillus species (read more). 

Tandem treatment of BV with antimicrobial therapy and probiotic supplementation, namely Lactobacillus reuteri and Lactobacillus rhamnosus, increased the abundance of indigenous Lactobacillus iners and Lactobacillus crispatus (read more). 

This was the rationale for developing Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14 for urogenital application with positive clinical outcomes reported (read more, more and more).

Urinary tract infection (UTI) treatment

Broad spectrum antibiotic treatment of women with UTIs, particularly recurring UTIs is increasingly seen as a less appropriate treatment than in the past because of the continued emergence of antibiotic resistance and the detrimental effects of broad-spectrum antibiotics on the beneficial microbiota of the host (patient).  There is greater research evaluating more targeted antibiotics and also prophylactic (preventative) treatment (read more) .

In a study carried out on women suffering recurring rates of UTI, participants received prophylactic bacterial lysate OM-89 daily for 90 days.  Bacterial lysate are broken up bacteria used to stimulate a specific immune response (similar to how a vaccine works).  At the end of the 6-month study, the frequency of UTIs decreased by 59.3% (read more).  This was an open study, without a control group, but was with a large population, so wide use of this preventative treatment may be a useful tool in decreasing UTI rates, especially for those women with recurring infections. There are commercial bacterial lysate products similar to Uro-Vaxom OM89 (read more) available in New Zealand (known as Uromune) (read more).

Evidence also suggests that bacterial species within the urinary tract and urogenital tract microbiomes, such as Lactobacillus crispatus, may act to protect against colonisation of uropathogens (read more). However, the mechanisms and fundamental biology of the urinary microbiome-host relationship are not understood (read more) and we need to gain a better understanding of how we get the Lactobacillus species to the right places in the urinary tract to make impact.

Specific probiotics widely available

Lactobacillus rhamnosus HN001™ and Lactobacillus acidophilus LA-14®

These are clinically-documented probiotic strains which are beneficial for vaginal health. These probiotics have been shown to promote healthy vaginal microbiota and a healthy vaginal pH in addition to having beneficial effects regarding bacterial vaginosis and vulvovaginal candidiasis when administered in conjunction with metronidazole or clotrimazole treatment, respectively.

These strains are safe for consumption (oral) and for topical use:

  • Long history of safe use;
  • No serious adverse effects in clinical studies in different target groups
  • Absence of risk genes as determined by genome mining
  • Well suited for intestinal survival:
    • High tolerance to acid and bile as present in the intestine;
    • Transient colonisation after consumption
    • Strong adhesion to human intestinal cell lines
  • Improves gastrointestinal health and well-being:
    • Improves microecology of the gut by increasing lactobacilli and bifidobacteria levels.

 Other probiotics being assessed (particularly for UTI prevention) include Lactobacillus gasseri and Lactobacillus crispatus (read more here, here and here).

Dietary treatments

Cranberries have long been identified as having a potential beneficial effect on reducing UTIs (read more).  It is thought that this is due to the presence of plant polyphenols, particularly anthocyanins (read more) which are prevalent in many purple plants, like blackcurrants (which we talk about in some of our other blogs, for their wide ranging benefits in brain, heart and lung health, read more here and here).


Vaginal dysbiosis is common, causing problems like thrush and/or urinary tract infections.  Often this dysbiosis is recurring and increasingly antibiotic resistant organisms are arising, which can present dangers for women, particularly those who are immunocompromised in hospital care. 

Unfortunately, research in this area is relatively thin on the ground, largely because some of the more promising solutions are not able to be patented, so commercial interests are less and financing/funding is hard to come by. 

From our research, we recommend prophylactically taking Lactobacillus species supplements orally on a daily basis for those regularly affected with vaginal dysbiosis and supporting this with a gut-healthy diet (we have other blogs on this, read more here and here).  It is also worth checking-out bacterial lysate treatment as an option with your medical practitioner if you are experiencing recurring UTIs.

Finally, the more we read about problems associated with vaginal dysbiosis and the sheer number of women affected, the more frustrated we are at the lack of research and progress in terms of finding solutions.  This is something we are thinking about and something we should all share and talk about as a priority in terms of urgently finding solutions.

Please contact Anna 027 4861418 or Darcy at 0275992255 at anytime if you have any comments, questions or thoughts.

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