There’s a peculiar phenomenon that plays an important role in female genitourinary health: the contiguity of the three orifices in the part of the body called the perineum: vagina, urethra leading to the bladder, and anus.
The nearness of these three orifices likely explains why and how, if a woman orally consumes, say, a probiotic containing certain bacterial species, the microbes will first colonize the colon, then the vagina, and then the bladder. (No, the bladder is not sterile, as we once believed.) There is no direct connection among the three, at least none that has been identified. So how do microbes in the colon access the vagina? And how do vaginal microbes access the bladder?
It must be via contiguity, i.e., the nearness of the three orifices. It’s a bit disturbing to think that fecal material can gain access to the vagina and bladder. This phenomenon can provide healthy effects such as colonization of the vagina and bladder with the bacterial species, Lactobacillus crispatus, that is the main keystone species of a healthy vagina that, in turn, colonizes the bladder and has been shown to reduce urge incontinence (peeing with coughing or laughing) and reduce the number of urinary tract infections (UTIs) in females who experience repeated UTIs. But it also means that unhealthy fecal species such as E. coli can colonize the vagina and bladder, causing “vaginosis,” or vaginal dysbiosis, and urinary tract infections.
It’s tempting to speculate whether translocation can also occur, i.e., microbes leave the GI tract through the intestinal wall and somehow migrate (via blood?) to the vagina and bladder. To my knowledge, this phenomenon has never been demonstrated with vagina or bladder. It has, however, been demonstrated in other areas of the body. The oral microbe that I have previously discussed, Fusobacterium nucleatum, that colonizes the mouth of most people but present at increased numbers in people with bleeding gums, gingivitis, and periodontitis, colonizes the colon. It has been shown that Fusobacterium does not reach the colon, however, via swallowing but via the bloodstream. Another oral microbe, Porphyromonas gingivalis, also associated with poor oral health, colonizes the brain where it is found at increased numbers in people with dementia. The fungal species, Candida albicans, can also be found densely populating the brains of people with dementia. The most likely way for fungi to colonize the brain is through the bloodstream.
Back to the perineum. Emerging insights into this little community are yielding insights that are contrary to so many previous prevailing concepts, leading to strategies to better manage female health. This has huge potential implications since a disrupted vaginal microbiome. a condition that afflicts around 30% of the female population, can lead to consequences such as miscarriage and premature labor. And the key to reduced incontinence and UTIs appears to lie in addressing the vaginal microbiome for many ladies.