Endometriosis is a chronic inflammatory condition characterized by endometrial-like tissue found outside the uterus. This tissue is commonly found on the ovaries, and is described as a “chocolate cyst” on ultrasound. It can also be found on the uterine ligaments, in the colon, and throughout the abdominal cavity. It can even be found on the diaphragm!
Just like the uterine lining, this tissue builds in response to the monthly hormonal cycle. Unlike the uterine lining, this tissue can’t degrade and shed as a period at the end of a cycle. Instead, it causes inflammation and swelling and leads to scar tissue buildup over time. This results in symptoms of extreme pain both during and outside of menstruation. Women also experience nausea, heavy periods, pain with intercourse, pain having a bowel movement, fatigue, and infertility.
Endometriosis is estimated to impact 5-15% of all women and can take upwards of 8 years to diagnose. There is currently no cure for it, and it’s typically managed with birth control pills, IUDs, or other hormone-modulating pharmaceuticals such as GnRH agonists and aromatase-inhibitors.
There is a need for alternative and supportive treatments for endometriosis. As naturopathic doctors, we frequently use botanicals, nutraceuticals, diet, and acupuncture, and see significant improvements!
Recent research indicates that the gut’s role—specifically the gut microbiome—may be another treatment avenue that needs to be explored.
What is the link between the gut and endometriosis?
The gut is now considered one of the central immune system homeostasis regulators. It contains an estimated 80% of the entire immune system! It’s well established that endometriosis is associated with a dysregulated immune system and elevated inflammatory markers. In addition, recent research hypothesizes that the gut’s health may be involved in both the onset and progression of endometriosis1.
A recent study compared the gut, vaginal, and cervical microbiota between women with Stage 3/4 endometriosis and healthy controls. Researchers found differences in the genus of bacteria between the two groups2. The main differences noted were an increased presence of Gardnerella bacteria in the cervical microbiota, and increased Escherichia and Shigella bacterial presence in the gut of patients with endometriosis compared to the controls2. It’s possible that the bacterial composition within the gut is different in women with endometriosis compared to controls.
In addition to the gut’s essential immune-regulating role, it’s also essential to estrogen detoxification. Estrogen isn’t a cause of endometriosis, but higher estrogen levels can exacerbate symptoms and worsen pain. Beta-glucuronidase is an enzyme within the gut that deconjugates estrogen.
This means that it allows estrogen to be re-absorbed into the bloodstream. Elevated beta-glucuronidase levels are associated with a gut microbiome imbalance, also known as dysbiosis. These increased levels are associated with diets that are higher in sugar, processed foods, and alcohol. As a result, they may be a possible target in endometriosis treatment due to their impact on circulating estrogen levels.
Can we target the gut to treat endometriosis?
Interestingly, some clinical studies found that impacting the gut can impact endometriosis symptoms in turn. One study used broad-spectrum antibiotics to alter the gut microbiome in mice who had surgically induced endometriosis4.
They found that after the antibiotics were administered, the endometriotic lesions were significantly smaller and inflammatory markers in peritoneal fluid were significantly reduced4. Even more interesting, the endometrial lesions and inflammatory markers were restored when the researchers re-populated the gut of the now-healthy mice with the faeces of mice that had endometriosis,4.
Probiotics have also been found to positively impact endometriosis. One study found that the specific strain, Lactobacillus gasseri OLL2809, significantly improved reported pain in endometrial patients compared to placebo after 12 weeks5.
The same researchers also found that giving Lactobacillus gasseri OLL2809 orally to mice with induced endometriosis significantly suppressed both the total weight and the total area of endometriotic lesions when compared to the control group6
- Endometriosis is a chronic inflammatory condition characterized by endometrial-like tissue found outside of the uterus
- The gut is now considered one of the central regulators of immune system homeostasis, containing an estimated 80% of the entire immune system
- It’s well established that endometriosis is associated with a dysregulated immune system and elevated inflammatory markers
- Both antibiotics and probiotics have been found to positively influence endometriosis signs and symptoms
- Laschke M, Menger M. The gut microbiota: a puppet master in the pathogenesis of endometriosis?. Am J Obstet Gynecol. 2016;215(1):68.e1-68.e4. doi:10.1016/j.ajog.2016.02.036
- Ata B, Yildiz S, Turkgeldi E et al. The Endobiota Study: Comparison of Vaginal, Cervical and Gut Microbiota Between Women with Stage 3/4 Endometriosis and Healthy Controls. Sci Rep. 2019;9(1). doi:10.1038/s41598-019-39700-6
- Flores R, Shi J, Fuhrman B et al. Fecal microbial determinants of fecal and systemic estrogens and estrogen metabolites: a cross-sectional study. J Transl Med. 2012;10(1):253. doi:10.1186/1479-5876-10-253
- Chadchan S, Cheng M, Parnell L et al. Antibiotic therapy with metronidazole reduces endometriosis disease progression in mice: a potential role for gut microbiota. Human Reproduction. 2019;34(6):1106-1116. doi:10.1093/humrep/dez041
- Itoh H, Uchida M, Sashihara T et al. Lactobacillus gasseri OLL2809 is effective especially on the menstrual pain and dysmenorrhea in endometriosis patients: randomized, double-blind, placebo-controlled study. Cytotechnology. 2010;63(2):153-161. doi:10.1007/s10616-010-9326-5
- Itoh H, Sashihara T, Hosono A, Kaminogawa S, Uchida M. Lactobacillus gasseri OLL2809 inhibits development of ectopic endometrial cell in peritoneal cavity via activation of NK cells in a murine endometriosis model. Cytotechnology. 2011;63(2):205-210. doi:10.1007/s10616-011-9343-z