Which are the causes of Endometriosis?

The exact cause of endometriosis remains unknown, but it is widely considered a multifactorial condition involving a complex interplay of hormonal, genetic, and immunological factors. Current scientific consensus suggests that retrograde menstruation—where tissue flows backward through the fallopian tubes—is a primary contributor, though other mechanisms like stem cell transformation and environmental influences are critical areas of ongoing research.

What is the underlying mechanism of endometriosis?

While the precise trigger for endometriosis is still being investigated, the most widely accepted theory is retrograde menstruation. In this process, endometrial-like tissue that should be shed during a period flows backward into the pelvic cavity, where it implants and grows on organs such as the ovaries, bowel, and bladder. However, because many people experience retrograde menstruation without developing the disease, researchers believe an abnormal immune response or a failure of the body to clear this misplaced tissue is required for endometriosis to take hold.

Is there a genetic component to endometriosis?

Yes, endometriosis has a strong hereditary component. Research indicates that if a first-degree relative—such as a mother or sister—has the condition, your risk of developing endometriosis is approximately 5 to 7 times higher than that of the general population. While no single "endometriosis gene" has been identified, genome-wide association studies (GWAS) have pinpointed several chromosomal loci that may predispose individuals to the disease. These genetic variations likely influence estrogen regulation, inflammation, and tissue remodeling.

What are the risk factors vs. the causes of endometriosis?

It is important to distinguish between a cause (the biological mechanism that creates the disease) and a risk factor (a demographic or behavioral trait associated with higher likelihood). While we do not fully understand the "causes," we have identified several well-documented risk factors:

• Early menarche: Starting menstruation at a young age (typically before 11).


• Short menstrual cycles: Cycles lasting less than 27 days.


• Heavy menstrual flow: Longer, heavier periods that may increase the volume of retrograde flow.


• Reproductive history: Nulliparity (never having given birth) is often associated with a higher diagnosis rate.


• Structural abnormalities: Physical obstructions in the reproductive tract that prevent normal menstrual egress.

What is the current state of research into the etiology of endometriosis?

Medical researchers are currently exploring several cutting-edge theories to better understand why endometriosis develops. One promising area of study focuses on the "stem cell theory," which suggests that circulating stem cells may differentiate into endometrial-like tissue in response to environmental or hormonal cues. Additionally, the role of the microbiome and systemic inflammation is gaining attention, as researchers study how the pelvic environment changes to allow these lesions to survive and thrive. With over 1,727 members sharing their experiences on DiseaseMaps.org, we are learning more about the diverse ways endometriosis manifests across different populations, helping to shape future clinical trials and diagnostic research.

Next steps

• Consult a gynecologist or a specialist in reproductive endocrinology if you suspect you have symptoms.


• Keep a detailed symptom diary to help your physician understand the frequency and intensity of your pain.


• Join the endometriosis community at DiseaseMaps.org to connect with others and stay updated on the latest research.


• Discuss diagnostic options, such as laparoscopic imaging or specialized ultrasound, with your healthcare provider.

Medical disclaimer: This content is for informational purposes only and does not constitute medical advice, diagnosis, or treatment; always seek the advice of your physician or other qualified health provider with any questions regarding a medical condition.

References

• NIH Genetic and Rare Diseases Information Center (GARD): Endometriosis.


• Orphanet: Endometriosis (ORPHA: 2167).


• World Health Organization (WHO): Endometriosis Fact Sheet.


• Endometriosis Foundation of America (EndoFound): Understanding the Science.