Mast Cells, Estrogen and Endometriosis: Understanding the Inflammatory Connection
Endometriosis is increasingly recognised as a condition that extends beyond the reproductive system.
While hormones — particularly estrogen — play a significant role, the immune system is also deeply involved in how the condition develops and how symptoms are experienced.
One area of growing research interest is the role of mast cells.
What Are Mast Cells?
Mast cells are a type of immune cell found throughout the body, particularly in tissues that interface with the external environment — such as the skin, gastrointestinal tract and pelvic organs.
They are best known for their role in allergic reactions, where they release substances like histamine in response to perceived threats.
However, mast cells are also involved in:
Regulating inflammation
Communicating with the nervous system
Influencing tissue repair
Modulating immune responses
The Link Between Mast Cells and Endometriosis
Recent research has identified increased numbers of activated mast cells in endometriosis lesions and surrounding tissues.
These cells release inflammatory mediators — including histamine, cytokines and growth factors — which may contribute to:
Local inflammation
Sensitisation of nerve pathways
Amplification of pain signals
At the same time, estrogen — a key hormone in endometriosis — appears to influence mast cell behaviour, increasing their activation and responsiveness.
This creates a potential feedback loop:
Estrogen promotes mast cell activation
Mast cells release inflammatory mediators
Inflammation and nerve sensitisation increase pain
Ongoing inflammation may further influence hormonal signalling
This interaction may be one reason why endometriosis pain can feel persistent, cyclical and difficult to manage.
Why This Matters Clinically
Understanding the immune component of endometriosis helps explain why symptoms are often broader than pelvic pain alone.
Some individuals may also experience:
Histamine sensitivity
Allergic-type symptoms
Skin reactions such as hives
Gastrointestinal disturbances
While not everyone with endometriosis will experience these patterns, their presence highlights the complexity of the condition.
Can Mast Cells Be Targeted?
Researchers are currently exploring whether targeting mast cell activity could play a role in endometriosis management.
However, mast cells are essential for normal immune function, which makes this area of treatment complex.
At present, there are no widely established therapies specifically targeting mast cells in endometriosis, and further clinical trials are needed to determine safety and effectiveness.
A Whole-Body Perspective
What this emerging research reinforces is that endometriosis is not solely a hormonal condition.
It involves interactions between:
The endocrine system
The immune system
The nervous system
For this reason, management often benefits from a multidisciplinary approach that considers inflammation, hormonal balance, nervous system regulation and overall health.
At Elgin House, we approach endometriosis through this integrated lens — supporting patients with personalised, evidence-informed care that reflects the complexity of the condition.
References
Anaf V et al. Mast cells and nerve fibers in endometriosis-associated pain. Human Reproduction.
Zhang X et al. Role of mast cells in inflammatory diseases and pain pathways. Journal of Neuroinflammation.
Bulun SE. Endometriosis. New England Journal of Medicine.
Konno R et al. Increased mast cell infiltration in endometriosis lesions. Fertility and Sterility.
Sikora J et al. The role of immune cells in endometriosis. Reproductive Biology and Endocrinology.
Theoharides TC et al. Mast cells, inflammation and chronic pain. Clinical Therapeutics.