Q&A: The Brain-Gut-Vagina Axis and How It Impacts Women's Health

After learning about the brain-gut connection some ten years ago, Betsy Greenleaf, DO, FACOOG, FACOG, MBA, started to wonder how the concept could apply to her work as a urogynecologist specializing in pelvic medicine. 

"I kept thinking about the gut-brain axis, and this light bulb went off, and I was like, ‘Wait a minute, there's a connection to the vagina too,'" Dr. Greenleaf said. “I was starting to see that when women's gut microbiomes were off, they were getting more recurrent urinary tract infections (UTIs) and vaginal dryness.”

When Dr. Greenleaf decided to dive deeper into the research, she unearthed a plethora of information linking the gut microbiome, the vagina microbiome, and a feedback loop to the brain which impacts women’s health concerns like fertility and sex drive. 

In February, Dr. Greenleaf spoke at the Integrative Healthcare Symposium about her findings and how healing the gut can positively influence vaginal health, fertility, and sex drive. After her presentation, we caught up with her to learn more about the brain-gut-vagina connection and how to apply the concept in clinical practice.

Integrative Practitioner: What is the relationship between the brain, the gut microbiome, and the vagina?

Dr. Greenleaf: A lot of people understand the brain-gut connection, especially in [the integrative healthcare] community. But, when I'm explaining it to somebody who's never heard of this before, I usually start by saying that the gut is where most of our happy hormones are made—over 90 percent of our serotonin and 80 to 90 percent of our immune system. I start there because it’s probably the easiest part to grasp. We know that if things are off in the gut, an individual is more susceptible to anxiety, depression, and recurrent illness.

Once we get the brain-gut connection explained, I move on to the vagina connection. The gut is the reservoir for the vaginal microbiome and, therefore, the urethral microbiome in women because of proximity of anatomy. So, if someone's getting recurrent UTIs or vaginal infections—that one's a little bit more obvious—then bacteria in the gut may be off.

Then it gets more confusing: they've shown that if the vaginal microbiome is off, there's a feedback loop through the vagus nerve to the brain to dampen all processes of reproduction, including sex drive. The body reacts by saying, 'Alright, now's not the time to reproduce, so we're going to just shut everything down.’

So, if we start in the brain, when someone is depressed, anxious, or under stress, that's going to feed back to the gut. And it’s going to cause more problems with leaky gut and aggravate the situation. Depression, anxiety, and stress are also going to raise their cortisol, which can increase the risk of yeast infections.

So that's how the brain is connected to the vagina. You also can't become sexually aroused unless the brain is functioning properly. It becomes very complicated, and it's hard to know where to start with all of it. But I think the simplest explanation is, if you're mentally balanced, and your gut is balanced, and the vagina is balanced, everything will be working properly.

Integrative Practitioner: How does this connection influence women’s health concerns about things like fertility and vaginal health?

Dr. Greenleaf: One of the biggest problems is the high rate of pelvic health problems in women; 80 percent of women will have a pelvic health problem at some point in their lives. And fertility is incredibly stressful—the fertility rate, depending on the stage you look at it, is around 19 percent. But if 80 percent of women are having a pelvic health problem at some point in their lives, and traditional medicine is not addressing it, this is a big, big problem.

We need to look more at these connections to really help women flourish. Just throwing antibiotics and slimy creams at them is not going to work; we need to be addressing the whole mind-body-spirit connection along with this trifecta of the brain-gut-vagina.

Integrative Practitioner: Are rates of pelvic problems like UTIs and vaginal yeast infections going up? If so, do you attribute that to diet?

Dr. Greenleaf: Yes. It’s funny; an article in the early 2000s connected eating chicken to an increased risk of UTIs. And I remember, as a traditional medicine doctor at that time, knowing nothing about integrative and functional medicine, thinking the article was insanely crazy. And now I realize the problem wasn't chicken in general, but the source of chicken in the study. It was probably highly contaminated with things like E. coli. Most likely, the increased risk of UTIs was due to higher levels of E. Coli in the subjects’ guts, which is the number one cause of women's UTIs.

We're seeing the same with increased rates of anxiety, depression, and obesity over the years. I think all this is coming down to gut health. If I had to say the main contributors, it would be diet, gut health, and stress levels. Those are the big factors that are feeding into all of this.

Integrative Practitioner: When a patient does have a UTI, don’t you have to treat them with antibiotics?  

Dr. Greenleaf: To a point, yes. Sometimes, you can get lucky with having them flush the bladder and just drink tons of fluids and use things like D-mannose and cranberry, but other times, you just need to do the antibiotics.

When I do choose antibiotics, I'm choosing things that are going to be less broad spectrum. When people come to the doctor with a UTI, they want relief instantly, but if I can get them to take something for their symptoms, like giving them an analgesic for the bladder just to numb things up, I prefer to wait and get the culture back. That way, I can get them an antibiotic that's going to target specific bacteria instead of giving them an atomic bomb that will throw everything off.

Integrative Practitioner: What are some preventative measures and targeted interventions for reoccurring UTIs and vaginal yeast infections that support the brain-gut-vagina axis?

Dr. Greenleaf: Let’s start with vaginal health: for prevention, if we can keep the vagina healthy, then the urinary tract tends to be healthy. And the vagina stays healthy because the gut is healthy, so diet is essential.

I joke with patients that they should only be eating foods that fall into four categories: It either has to walk, grow, fly, or swim. And Doritos and Twinkies don't grow on trees. I also suggest a serving of fermented food every day if they can tolerate it, and if they can't, then we go back to the drawing board. It’s about getting to the basics, including quality sleep and drinking more fluids.

The problem is, you can take all the probiotics in the world orally or put them in your vagina, but that’s not going to keep the vaginal microbiome balanced. You need some support for the tissue. Naturally, when we're younger, we have estrogen that causes active growth of the vaginal tissue, which will slough off and contains glycogen which feeds the healthy bacteria. Health vaginal tissue keeps everything balanced, but stress, antibiotics, and hormones can throw it off.

We need healthy vaginal tissue to keep feeding the probiotics. A postmenopausal woman who's stressed, let’s say, may have to use topical hormones or some of the regenerative therapies. There are many regenerative therapy options on the market now, like vaginal red-light therapy, laser therapy, platelet-rich plasma therapy, and something called carboxy therapy, which uses carbon dioxide gel to attract oxygen in the tissue.

The vaginal tissue needs to be thick and healthy so it can continue to feed healthy bacteria like Lactobacillus. As long as the vaginal tissue is healthy, it’s going to help decrease the risk of UTIs and boost libido and fertility. So, supporting the brain-gut-vagina axis is going to include a combination of probiotics and products that support the vaginal tissue.

Editor's Note: This interview has been edited and condensed.