Fewer protective ‘good’ bacteria in the vagina may result in a greater risk of developing ovarian cancer.
Professor Martin Widschwendter’s team found that changes in the number of ‘good’ bacteria can be used to build a clearer picture of a woman’s risk of developing ovarian cancer. ‘Good’ bacteria in the vagina normally help prevent overgrowth of other ‘bad’ types of bacteria.
The study found that women with ovarian cancer had far fewer ‘good’ bacteria, called lactobacilli, in their vagina. This lower level was also seen in women with an inherited BRCA1 gene alteration (a 40x higher risk of developing ovarian cancer in their lifetime).
The research strongly supports growing evidence that the vaginal microbiome is important to health. Further research hopes to show that re-introducing ‘good’ bacteria into the vagina will reduce a woman’s risk of the disease.
During the study, samples were taken from the cervix and vagina using a cervical screening brush from:
- women who had been diagnosed with ovarian cancer
- women who were at high risk of developing ovarian cancer
- and women who were not at a higher risk of developing the disease
It is hoped that with further research, the amount of ‘good’ bacteria could be used as another indicator of ovarian cancer risk.
This study was funded by the EU’s Horizon 2020 Research and Innovation Programme (H2020 FORECEE under grant agreement 634570), the EU’s Horizon 2020 European Research Council Programme (H2020 BRCA-ERC under grant agreement 742432), and The Eve Appeal.
Young women and people with gynae organs who have a BRCA1/2 alteration are faced with difficult decisions around reducing their risk of breast and ovarian cancer.
MEET HAYLEY
Hayley Minn reflects on these choices since finding out she carried the alteration when she was 23.
I was 27 when I had my mastectomy. Too young to be worrying about cancer and no matter how much I loved my boobs, I knew that getting rid of them could save my life. I’ve been told I should seriously start thinking about having a hysterectomy when I’m 35, which is extremely scary as I do want children. So anything that buys me more time and reassures me that ovarian cancer isn’t developing, is a game-changer for me.
FAQs: What is the vaginal biome and why is it important?
What does ‘vaginal biome’ mean?
The vaginal biome is the ecosystem that exists in the vagina. Just like our gut, the vagina contains bacteria, fungi and viruses which together make up the vaginal biome.
Does this mean that like the gut, the vagina has good and bad bacteria?
Yes, exactly. The healthy (good, friendly) bacteria in the vagina, known as lactobacilli, normally outnumber the number of bad, ‘unfriendly’ bacteria called anaerobes.
What does the friendly bacteria do?
The vaginal lactobacilli play a hugely important role in vaginal health. Lactobacilli release lactic acid and hydrogen peroxide which creates an acidic environment in the vagina. An acidic pH in the vagina (between 3.8 and 4.5) and maintaining this pH balance is vital to keeping it healthy. These friendly bacteria act as a protective barrier that stops the growth of bad bacteria and potential infections.
What happens when there are more bad bacteria and fewer healthy bacteria?
When there’s an imbalance in the vagina’s pH levels, bad bacteria can grow. These bad bacteria can then develop into infections such as bacterial vaginosis (BV), the most common vaginal infection in women under 45 and the most common cause for abnormal discharge.
What are the symptoms of bacterial vaginosis (BV)?
Around 50% of people with bacterial vaginosis don’t experience any symptoms, but the main sign is unusual discharge that has a strong, fishy smell. The colour of your discharge may become more grey/white and have a thinner, more watery consistency than usual. BV needs to be treated with antibiotics, so if you are experiencing these symptoms, please make an appointment at your GP practice or sexual health clinic.
Can bad bacteria in the vagina cause any other problems?
Unfortunately, yes! Bacterial infections in the vagina can travel further up the gynaecological tract, into the womb, ovaries and Fallopian Tubes and cause something called pelvic inflammatory disease (PID). Around 1 in 4 cases of PID are caused by STI’s such as chlamydia. Pelvic inflammatory disease is a common condition and when caught early, is easily treated with a course of antibiotics.
What are the symptoms of pelvic inflammatory disease?
There isn’t one stand-out symptom of pelvic inflammatory disease, but most people experience a mild form of one or more of the following: pelvic pain, pain during sex, painful urination, bleeding in between periods, bleeding after sex, heavy and/or painful periods, a yellow/green vaginal discharge.
Is it true that pelvic inflammatory disease can lead to infertility?
In around 1 in 10 cases of pelvic inflammatory disease, yes. This is because PID can scar and narrow the Fallopian Tubes, making it difficult for an egg to pass through from the ovaries to the womb, this in turn can increase the likelihood of an ectopic pregnancy, which is when the egg is fertilised in a Fallopian Tube rather than the womb.
Can bad vaginal bacteria cause cancer?
Newly published research by UCL and funded by The Eve Appeal and Horizon 2020 shows that women with ovarian cancer have a significant reduction in friendly vaginal bacteria (lactobacilli), compared to those who don’t have the disease. This suggests that the more lactobacilli found in a woman’s vagina, the lower her risk of ovarian cancer. The next step is to investigate the presence of bad bacteria in the Fallopian Tubes, which is where most ovarian cancers begin. So, for now we can’t say that the unfriendly bacteria cause ovarian cancer, but there is certainly evidence showing the protective benefits of healthy bacteria.
So, what can I do to maintain a healthy vaginal pH and stop the bad bacteria?
The vaginal biome is complicated and sensitive. Many things can alter the vagina’s pH balance which increases the risk of infection. Some altering factors can’t really be avoided, for example blood has a neutral pH of 7.4, so when menstruating (being on your period) the presence of blood in the vagina will increase its pH levels. Whilst on the topic of bodily fluids, semen also has a similar pH to blood (7.1-8). Using condoms will prevent the semen from altering the vagina’s pH balance, but this is of course difficult to avoid for people who are trying to get pregnant, or can’t/prefer not to use condoms. The easiest ways of trying to maintain a healthy pH balance are actually some of most effective. Here are the top things you can do:
If you use tampons, change them regularly. Many tampon brands use ingredients that aren’t particularly kind to the vaginal biome, and so it might be worth investigating more ‘vagina friendly’ tampons or consider using different forms of period products.
Avoid ‘feminine hygiene’ products. Using perfumed/scented products in or around your vagina is harmful. Wipes, washes, any deodorant-based product for your genitals usually have a high pH level, which disrupts the vagina’s natural balance and can cause irritation. The vagina is self-cleaning, so these products really aren’t necessary. If you find that your discharge is unpleasant smelling, or notice something different to your ‘normal’, please seek advice from your doctor rather than trying to cover up the smell with perfumed products.
Don’t douche. Douching essentially means rinsing out the vagina with water, sometimes combined with cleaning chemicals. Douching will do nothing other upset the pH balance of your vagina. Many people douche for hygiene reasons but it’s actually an unhygienic process and will increase your risk of infection.
Discover more
Martin’s project, 4C, to develop one screening test for four key cancers: breast, womb, ovarian and cervical, has led to many discoveries. Find out more his work.
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