What is the Best Probiotic Supplement for Women?

Kathy Wheddon Nutritional Therapist DipION

Research shows that different probiotic strains (types) do different things, which means they are not one-size-fits-all. Therefore, the best one for you depends on your individual needs. Many probiotics are beneficial for both women and men, but there are several strains that have been shown to support women’s health specifically. No matter what your health concern, this article will pinpoint the best probiotics for you.

Woman smiling
To stay happy and healthy, don't forget your 'intimate' flora!

Where should I start?

When we are looking at the best probiotics for women to take, we need to consider the needs of two separate anatomical areas, namely the GI tract and the urogenital tract.

Due to the proximity of the vagina to the anus, it is much easier for pathogenic bacteria to cross over from the GI tract to the urogenital tract in women than in men. This can then go on to cause dysbiosis. The flora of a healthy vagina is made up of different strains of bacteria to the gut flora, and hence should be considered separately when you are choosing a probiotic.

The benefits of probiotics for women are evident in the gut and the intimate area. A large amount of research demonstrates that some probiotic strains are more appropriate than others to support female intimate health. Read on to find out more about the importance of choosing the right strain.

1) Best probiotics for women's vaginal health:

New and wider-reaching clinical applications for probiotics are emerging all the time. One of these growing areas of research is the role of probiotics in women’s intimate health.

Beneficial flora, or probiotics, inhabit the urogenital tract (spanning the urinary and vaginal tract in women) as well as the gut. In the vagina and urinary tract, probiotics are thought to exert many of the same beneficial effects as they would in the gut. Their presence limits the likelihood of pathogenic bacteria and yeasts being able to overgrow.

Clinical trials have shown that a number of strains of Lactobacillus are particularly effective for female intimate health problems, such as cystitis, thrush and bacterial vaginosis. These specific strains (in particular Lactobacillus rhamnosus GR-1® and Lactobacillus reuteri RC-14®) have been clinically trialled to survive transit through the gut, and then successfully colonise the vagina and bladder. This is where they exert their beneficial effects.

It is thought that most urogenital infections, like thrush, cystitis and bacterial vaginosis, stem from pathogens in the intestines. This is due to the ease with which microorganisms can transfer from the anus to the vagina, and then spread via the urethra to the bladder to the urogenital tract. It seems a reasonable assumption to make, then, that taking probiotic supplements can positively affect the flora of our urogenital tracts, and therefore help UTIs and vaginal infections.

There have been a number of clinical trials that support this theory, including a 2004 studyat the Canadian Research and Development Centre for Probiotics. This study, a randomised, placebo-controlled trial, showed that the vaginal microflora in women with Bacterial Vaginosis (BV) was restored to a more favourable, Lactobacilli-dominant environment following 2 months of a daily oral intake of the probiotics Lactobacillus rhamnosus GR-1®and Lactobacillus reuteri RC-14®.

Mechanisms of action 'For Women'

An Italian study2 in 2004 looked at the specific strains of Lactobacilli that are able to survive the gastrointestinal tract intact in order to then colonise the vagina. The study summarised that "L. rhamnosus GR-1® and L. reuteri RC-14® can be delivered to the vaginal environment even if they are taken orally" and "Their administration results in significant changes in the vaginal flora in terms of increased Lactobacilli presence…"

As always, we should emphasise that not all strains are equal when it comes to probiotics, and there is no exception for probiotics for women's health. An article3 in the ‘World Journal of Urology’ in 2006 states that when it comes to the prevention of urinary tract infections, not all Lactobacilli are effective. It named Lactobacillus rhamnosus GR-1® and Lactobacillus reuteri RC-14®, alongside a third strain Lactobacillus reuteri B-54 as the only strains that have demonstrated their ability to survive the digestive tract and then successfully colonise the vagina and bladder.

Due to fluctuating hormone levels some women find that they may become more prone to vaginal dysbiosis at certain points in their menstrual cycle. If intimate health is a concern for you, then a supplement that contains the well-researched Lactobacillus rhamnosus GR-1®and Lactobacillus reuteri RC-14® strains of probiotic might suit you best.

2) Best probiotics for women's digestive health

As mentioned, the vaginal flora will require different strains to those recommended for gut health. Whilst the question of the best probiotic strains for digestive health conditions is not gender-specific, here we explore a few digestive conditions which are reportedly more common in women.


One symptom to look at when discussing probiotics specifically for female digestive health, is the problem of bloating, which is reported to be much more common in women than men. This can either be a constant problem, or the bloating can be cyclical and worsen at certain points in the menstrual cycle, due to fluctuating hormone levels.

Bloated woman

Whilst both situations have slightly different physiological causes, the result is the same; digestion is impaired and food is not effectively broken down, causing bloating and wind.

Probiotics will help to rectify the root of bloating, which is digestive dysfunction. Lactobacillus acidophilus NCFM® was found in a double-blind, randomised, controlled clinical trial to improve bloating by 73%4.


If constipation is involved (again, a condition reported to be much more common in women, often during menstruation and pregnancy), a probiotic supplement containing B. lactis BB-12® would be the best. Bifidobacterium lactis BB-12® along with FOS (a prebiotic) helps gently ease/discourage constipation, as supported by one of the largest ever clinical trials on probiotics5. This strain, like many other probiotics, works by encouraging the proliferation of good bacteria in the colon. 

Avoiding constipation is important when managing hormonally related conditions, as ‘old’ or spent hormones, that have been processed by the liver, are eliminated via the faeces. When constipated, these hormones can be re-absorbed back into the bloodstream from the faecal matter due to the longer transit time, leading to hormonal disturbances.

Health professionals can read more about the research using this strain in the Probiotics Database: Bifidobacterium lactis BB-12®.

Foods that prevent constipation should also be considered, alongside specific herbs and nutrients that help to balance hormones, such as magnesium and vitamin B6. (N.B. it is always advised that you should seek the advice of a qualified healthcare professional to find the most suitable combination of supplements for your needs).

For more information regarding probiotics and digestive health, read about probiotics and IBS here.

Go with your gut feeling

When selecting a probiotic supplement, choose the one that feels right for you. Men and women have the same basic flora in the gut, so gender on its own is not a factor when it comes to selecting the right probiotic for digestive health. The only implication of gender on our balance of intestinal flora comes from the effect that the various sex hormones have on it, and the tendency for some women to experience GI upset at certain points in their menstrual cycle.

It is also worth noting that side effects of probiotics for women are rare, making these supplements a popular choice for daily maintenance of gut and intimate health. 

In Summary

  • Probiotic supplements for women are beneficial for gut health and intimate health.
  • Probiotics can help to limit the overgrowth of harmful bacteria and yeasts that contribute to the development of gut and intimate health issues.
  • The vagina and urinary tract require different bacteria to the gut to maintain a healthy microbiome. Therefore, choose specific probiotic strains that are well researched for their effects in each specific area.
  • The best probiotic supplements for intimate health contain probiotic strains such as Lactobacillus rhamnosus GR-1®Lactobacillus reuteri RC-14® and Lactobacillus reuteri B-54.
  • The best probiotics for common gastrointestinal issues experienced by women, such as bloating and constipation, include Lactobacillus acidophilus NCFM® and Bifidobacterium lactis BB-12®.

You can read more about women and probiotics here: 

Probiotics & Bacterial Vaginosis

All About Your Vaginal Flora


  1. Reid, G., Burton, J., Hammond, J. and Bruce, A. (2004). Nucleic Acid-Based Diagnosis of Bacterial Vaginosis and Improved Management Using Probiotic Lactobacilli. Journal of Medicinal Food, 7(2), pp.223-228.
  2. Morelli, L., Zonenenschain, D., Del Piano, M. and Cognein, P. (2004). Utilization of the Intestinal Tract as a Delivery System for Urogenital Probiotics. Journal of Clinical Gastroenterology, 38(Supplement 2), pp.S107-S110.
  3. Reid, G. and Bruce, A. (2005). Probiotics to prevent urinary tract infections: the rationale and evidence. World Journal of Urology, 24(1), pp.28-32.
  4. Faber, S.M. (2000). ‘Treatment of abnormal gut flora improves symptoms in patients with irritable bowel syndrome’. American Journal of Gastroenterology, 95(9):2533.
  5. Eskesen, D. et al. (2015), ‘Effect of the probiotic strain Bifidobacterium animalis subsp. lactis BB-12® on defecation frequency in healthy subjects with low defecation frequency and abnormal discomfort: a randomised, double-blind, placebo-controlled, parallel-group trial’, British Journal of Nutrition, Nov 28: 114(10):1638–1646.