I’ll never forget when I worked for Dr. Oz back in 2005 and he got a question on his radio show from a caller on douching (which, I would realize years later, was really a question about the vaginal microbiome). What he said would bring him attention for decades to come. Don’t douche! The vagina is a self-cleaning oven.
Robin’s Short Version
- Diversity Is Bad: Unlike the gut, a healthy vaginal microbiome is dominated by L. crispatus—more bacterial diversity signals worse outcomes.
- pH Is Defense: L. crispatus produces lactic acid to hold vaginal pH between 3.8–5, actively blocking the growth of harmful organisms.
- Check Your Lube: Lubricants with chlorhexidine gluconate harm healthy lactobacillus—choose one formulated to match vaginal pH.
He was right. Don’t douche. But what we didn’t fully understand then is the role the microbiome plays in overall vaginal health, defining exactly why the vagina is in fact a self-cleaning oven. The medical community has spent a ton of time talking about the gut microbiome but lately I’ve been super interested in how our health is impacted and supported by the other microbiomes that get less airtime. Think: the skin microbiome (which I’ll cover in a future newsletter) and yes, the vaginal microbiome.
I thought of this self-cleaning oven moment recently when I attended a launch event for my friends at Seed (who I’m partnering with on content this fall, including this newsletter) which just launched a new probiotic designed to support the vaginal microbiome.
If you have a vagina—Or care about someone who does!—you may find it as fascinating as I have to dive into the bacterial ecosystem important for everything from supporting vaginal immunity, to odor, to lubrication.
Read on for the research and what I’m personally doing to make sure all my microbiomes are as healthy, vibrant, and resilient as possible.
The research says
The vaginal microbiome is a dynamic ecosystem and a key driver of gynecological, urogenital, and reproductive health. Activities like douching disrupt that ecosystem, causing an overgrowth of potentially harmful bacteria that can lead to all kinds of uro-gynecological health issues. Yet—despite Dr. Oz’s self-cleaning PSAs—nearly 20% of women still do it, according to the U.S. Office on Women’s Health.
The optimal vaginal ecosystem
A healthy vaginal pH level is between 3.8 and 5 (slightly acidic, like a tomato), according to a 2021 study.
The optimal vaginal microbiome is also dominated by a superabundance of one type of bacteria—Lactobacillus Crispatus—which is associated with favorable health outcomes. Put another way, bacterial diversity here is bad. Ideally, L. crispatus runs the show.
As far as good bacteria go, L. crispatus is a super-defender. It produces lactic acid to keep vaginal pH in balance and limit the growth of potentially harmful organisms.
The vaginal microbiome out of balance
Just like your gut microbiome, the vaginal microbiome is malleable and easily influenced—lots of seemingly innocuous things can alter the balance. Beyond douching—any product that comes into contact with the vagina can impact the microbiome.
Take lube, for example. Lubricant can not only impact the pH balance of the vagina (which is why it’s important to choose a lube that matches vaginal pH), but have antimicrobial effects. (Which is bad for a microbiome.) Lube containing chlorhexidine gluconate is particularly bad for the growth of healthy lactobacillus, according to a 2021 in vitro study.
