TL;DR
Endometriosis is influenced by hormones and inflammation. New research reviews show that environmental chemicals that disrupt hormones may increase the risk or severity of endometriosis, especially with long-term or early-life exposure.
What is Endometriosis?
Endometriosis is a chronic condition in which tissue similar to the lining of the uterus grows outside the uterus. It often causes pain, heavy periods, fertility problems, and inflammation. While genetics and hormones play a role, researchers have also been studying whether environmental chemicals may increase the risk or severity of this condition.
Early Research Linking Endometriosis to Environmental Chemicals
More than 20 years ago, scientists began noticing a pattern. Animal studies showed that exposure to certain industrial chemicals—such as dioxins and chemicals similar to PCBs—was linked to a higher rate and greater severity of endometriosis. The higher the level of these chemicals in the body, the worse the disease appeared to be [1].
Around the same time, human studies found that women with endometriosis were more likely to have higher blood levels of certain PCBs, especially those that interfere with estrogen signaling [2,3]. These early findings raised concern, but they did not provide the full picture.
What More Recent Research Tells Us
In the last few years, larger and more comprehensive reviews have pulled together results from dozens of animal and human studies. These reviews focus on a group of substances known as endocrine-disrupting chemicals (EDCs)—chemicals that can interfere with normal hormone signaling.
A major 2020 review in The Lancet Diabetes & Endocrinology reported strong human evidence linking EDC exposure to several reproductive conditions, including endometriosis, polycystic ovary syndrome (PCOS), reduced fertility, and breast cancer [4]. The authors also noted links between these chemicals and metabolic and immune-related problems.
A 2023 review in the International Journal of Molecular Sciences focused specifically on women’s reproductive health and endometriosis. The authors concluded that environmental toxins may contribute to endometriosis by altering estrogen activity, immune function, and inflammatory pathways—especially when exposure occurs early in life [5].
Other reviews have described how pesticides, plastic-related chemicals (such as bisphenols and phthalates), and persistent pollutants can disrupt ovarian hormone production and uterine tissue structure [6].
A Broader Health Pattern
Research has also found that women with endometriosis often have higher rates of other inflammatory or immune-related conditions, such as allergies, thyroid disorders, and autoimmune diseases. This suggests that endometriosis may be part of a broader pattern of immune and hormonal imbalance—one that environmental exposures may influence.
The Bottom Line
Endometriosis is a complex condition with many contributing factors. Modern research supports the idea that environmental endocrine-disrupting chemicals may be one of several influences, particularly through their effects on hormones, inflammation, and immune function. This does not replace other explanations, but it adds an important layer to how researchers understand the disease.
Reducing unnecessary chemical exposure is not a treatment for endometriosis—but understanding these environmental factors may help explain why the condition has become more common and more severe over time.
References:
- Toxicological Sciences, Volume 59, Issue 1, January 2001, Pages 147–159 Serum Levels of TCDD and Dioxin-like Chemicals in Rhesus Monkeys Chronically Exposed to Dioxin: Correlation of Increased Serum PCB Levels with Endometriosis
- Human Reproduction. 2005;20(1):279–285. Environmental PCB exposure and risk of endometriosis
- Fertility and Sterility. 2005;84(2):305–312. Increased dioxin-like compounds in the serum of women with peritoneal endometriosis and deep endometriotic (adenomyotic) nodules
- The Lancet Diabetes & Endocrinology. 2020;8:703–718. Endocrine-disrupting chemicals: Implications for human health.
- International Journal of Molecular Sciences. 2023;24(6):5682. Endocrine Disruptor Compounds in Environment: Focus on Women’s Reproductive Health and Endometriosis.
- JBRA Assisted Reproduction. 2019;23:154. Environmental toxins and women’s reproductive health.
