Conditions like endometriosis, adenomyosis, and polycystic ovary syndrome (PCOS) are often discussed in the context of reproductive health or hormonal imbalance. But researchers are beginning to explore deeper connections—specifically, whether autoimmunity plays a role in these diseases.
Let’s break down what the science says—and what questions remain unanswered.
Conditions like endometriosis, adenomyosis, and polycystic ovary syndrome (PCOS) are often discussed in the context of reproductive health or hormonal imbalance. But researchers are beginning to explore deeper connections—specifically, whether autoimmunity plays a role in these diseases.
Let’s break down what the science says—and what questions remain unanswered.
The immune system is designed to protect the body from threats like viruses and bacteria. But in autoimmune diseases, the immune system becomes misguided and starts attacking the body’s own cells and tissues.
Common autoimmune conditions include:
• Lupus
• Rheumatoid arthritis
• Hashimoto’s thyroiditis
• Multiple sclerosis
Symptoms vary widely, but many autoimmune conditions involve chronic inflammation, pain, fatigue, and a pattern of flare-ups.

Endometriosis occurs when tissue similar to the uterine lining grows outside the uterus—causing pain, inflammation, and sometimes infertility. While its exact cause is still debated, many researchers believe that the immune system fails to clear out these rogue cells effectively.
Several studies have found:
• Women with endometriosis often have higher levels of inflammatory markers, like cytokines and prostaglandins.
• Natural killer (NK) cell activity is lower in women with endometriosis, impairing the immune system’s ability to destroy misplaced cells.
• There are elevated autoantibodies in some patients, suggesting an autoimmune component.
Some scientists now consider endometriosis to be a non-classical autoimmune disease—showing many features of one without meeting all diagnostic criteria.
• NIH - Immune dysfunction in endometriosis: https://pubmed.ncbi.nlm.nih.gov/30664929/
• Cleveland Clinic - Endometriosis and the Immune System: https://health.clevelandclinic.org/endometriosis-and-the-immune-system/
Adenomyosis is sometimes called the "sister disease" of endometriosis. It occurs when endometrial tissue grows into the muscular wall of the uterus. It's less studied, but immune abnormalities have also been observed.

Research is still emerging, but here’s what we know:
• Women with adenomyosis show immune cell changes and chronic inflammation within the uterus.
• Some studies report increased macrophage and mast cell activity—cells involved in both immune defense and inflammation
• The condition often coexists with endometriosis, raising questions about shared immune pathways.
While it’s too early to label adenomyosis an autoimmune disorder, it may involve an immune imbalance that contributes to symptoms.
• Frontiers in Immunology - Immunopathogenesis of Adenomyosis: https://www.frontiersin.org/articles/10.3389/fimmu.2021.796273/full
Polycystic ovary syndrome (PCOS) is primarily known as a hormonal disorder involving androgen excess and insulin resistance. However, there’s growing interest in its immune connections, especially in women with chronic inflammation or thyroid issues.
Emerging links include:
• Hashimoto’s thyroiditis (an autoimmune thyroid disorder) is more common in women with PCOS.
• Inflammatory markers like C-reactive protein (CRP) are often elevated in PCOS patients.
• Some PCOS patients have anti-ovarian antibodies, suggesting potential autoimmunity.
Still, the autoimmune theory is more speculative in PCOS than in endometriosis.
Further reading:
• Journal of Clinical Endocrinology & Metabolism - PCOS and Autoimmune Disease: https://academic.oup.com/jcem/article/106/9/e3536/6280755

If immune dysfunction is part of the puzzle, treatment strategies may need to shift. Many women with endometriosis, adenomyosis, or PCOS are treated solely with hormone suppression—but if autoimmunity is involved, we may also need to address inflammation, gut health, and immune regulation.
There’s also hope that newer treatments—like immunomodulatory therapies or even personalized nutrition and lifestyle interventions—could improve outcomes when tailored to the immune system’s role.
We don’t yet have all the answers, but the research is evolving. Endometriosis, adenomyosis, and PCOS may not be traditional autoimmune diseases—but they often coexist with immune dysfunction, and the overlap deserves attention. At Our Daughters Foundation, we believe in honoring women’s voices, advocating for deeper research, and pursuing whole-body solutions.
If you’ve experienced overlapping conditions like endo, thyroid disease, or unexplained inflammation—you’re not alone.
The immune system is designed to protect the body from threats like viruses and bacteria. But in autoimmune diseases, the immune system becomes misguided and starts attacking the body’s own cells and tissues.
Common autoimmune conditions include:
• Lupus
• Rheumatoid arthritis
• Hashimoto’s thyroiditis
• Multiple sclerosis
Symptoms vary widely, but many autoimmune conditions involve chronic inflammation, pain, fatigue, and a pattern of flare-ups.

Endometriosis occurs when tissue similar to the uterine lining grows outside the uterus—causing pain, inflammation, and sometimes infertility. While its exact cause is still debated, many researchers believe that the immune system fails to clear out these rogue cells effectively.
Several studies have found:
• Women with endometriosis often have higher levels of inflammatory markers, like cytokines and prostaglandins.
• Natural killer (NK) cell activity is lower in women with endometriosis, impairing the immune system’s ability to destroy misplaced cells.
• There are elevated autoantibodies in some patients, suggesting an autoimmune component.
Some scientists now consider endometriosis to be a non-classical autoimmune disease—showing many features of one without meeting all diagnostic criteria.
• NIH - Immune dysfunction in endometriosis: https://pubmed.ncbi.nlm.nih.gov/30664929/
• Cleveland Clinic - Endometriosis and the Immune System: https://health.clevelandclinic.org/endometriosis-and-the-immune-system/
Adenomyosis is sometimes called the "sister disease" of endometriosis. It occurs when endometrial tissue grows into the muscular wall of the uterus. It's less studied, but immune abnormalities have also been observed.

Research is still emerging, but here’s what we know:
• Women with adenomyosis show immune cell changes and chronic inflammation within the uterus.
• Some studies report increased macrophage and mast cell activity—cells involved in both immune defense and inflammation
• The condition often coexists with endometriosis, raising questions about shared immune pathways.
While it’s too early to label adenomyosis an autoimmune disorder, it may involve an immune imbalance that contributes to symptoms.
• Frontiers in Immunology - Immunopathogenesis of Adenomyosis: https://www.frontiersin.org/articles/10.3389/fimmu.2021.796273/full
Polycystic ovary syndrome (PCOS) is primarily known as a hormonal disorder involving androgen excess and insulin resistance. However, there’s growing interest in its immune connections, especially in women with chronic inflammation or thyroid issues.
Emerging links include:
• Hashimoto’s thyroiditis (an autoimmune thyroid disorder) is more common in women with PCOS.
• Inflammatory markers like C-reactive protein (CRP) are often elevated in PCOS patients.
• Some PCOS patients have anti-ovarian antibodies, suggesting potential autoimmunity.
Still, the autoimmune theory is more speculative in PCOS than in endometriosis.
Further reading:
• Journal of Clinical Endocrinology & Metabolism - PCOS and Autoimmune Disease: https://academic.oup.com/jcem/article/106/9/e3536/6280755

If immune dysfunction is part of the puzzle, treatment strategies may need to shift. Many women with endometriosis, adenomyosis, or PCOS are treated solely with hormone suppression—but if autoimmunity is involved, we may also need to address inflammation, gut health, and immune regulation.
There’s also hope that newer treatments—like immunomodulatory therapies or even personalized nutrition and lifestyle interventions—could improve outcomes when tailored to the immune system’s role.
We don’t yet have all the answers, but the research is evolving. Endometriosis, adenomyosis, and PCOS may not be traditional autoimmune diseases—but they often coexist with immune dysfunction, and the overlap deserves attention. At Our Daughters Foundation, we believe in honoring women’s voices, advocating for deeper research, and pursuing whole-body solutions.
If you’ve experienced overlapping conditions like endo, thyroid disease, or unexplained inflammation—you’re not alone.
Your support can transform lives. Every donation helps us fund research, advocate for better care, and provide essential grants to women facing debilitating conditions.
Your support can transform lives. Every donation helps us fund research, advocate for better care, and provide essential grants to women facing debilitating conditions.


Sharing a post originally written by Dr. Luka Nićin (VC at Pace Ventures | PhD in Molecular Medicine | MBA in Biotech Strategy). Whether your motivation is compassion, easing the pain of someone you love, or even pure capitalism—we see you, and we applaud the work you’re doing to raise awareness and push for answers. Let’s keep making noise together. -Kara
"1 in 10 women. 7–10 years to diagnosis. $100B+ annual economic burden.
That’s endometriosis.
And yet it’s historically received less than 0.1% of NIH funding compared to cancer or cardiovascular disease.
Women’s pain hasn’t just been ignored — it’s been systematically underinvested in.
The opportunity?
1. Therapeutics beyond blunt hormonal tools.
2. Diagnostics that cut a decade-long delay to months.
3. Digital biomarkers that finally personalize care.
4. Fertility crossover where payers and employers are already spending.
The women’s health market isn’t niche. It’s half the population.
Endometriosis isn’t only an unmet need. It’s a generational venture opportunity hiding in plain sight.
Let’s get real.
For decades, women’s pain has been treated as background noise.
Dismissed. Normalized. Ignored.
Endometriosis is the perfect case study. It affects 1 in 10 women of reproductive age. Diagnosis takes an average of 7–10 years. Current treatments are outdated, invasive, or woefully inadequate. And yet: endometriosis research has historically received less than 0.1% of NIH funding compared to cancer or cardiovascular disease.
This isn’t just a moral failure. It’s a market failure.
Why It’s Underfunded
Bias baked into science. Women were excluded from most clinical trials until the 1990s. We’re still living with the hangover.
Symptoms dismissed. Pain, fatigue, infertility? Too often chalked up as “psychological” or “part of being a woman.” That stigma slowed research, trials, and drug approvals.
Fragmented patient voice. Endo patients don’t die quickly, they suffer chronically. Chronic suffering doesn’t mobilize lobbying dollars like mortality does.
The result: a $100B+ annual economic burden (missed work, failed fertility treatments, repeat surgeries) with barely a handful of commercial therapies in market.
Where the Opportunity Lies
Novel therapeutics. Hormone modulators and non-hormonal targets are only scratching the surface. There’s room for precision medicines, immune-modulating therapies, and gene-driven discovery.
Diagnostics. Non-invasive, early detection tools would collapse that 10-year diagnostic delay — creating the wedge for earlier intervention and better trial design.
Digital biomarkers + AI. Tracking pain patterns, symptom clusters, and treatment responses at population scale can finally personalize therapy.
Fertility crossover. Endo sits at the intersection of women’s health and reproductive medicine — a convergence where payers, employers, and governments are finally willing to spend.
Why This Is Venture-Scale
The women’s health market is not “niche.” It’s half the population.
Endometriosis alone represents a multi-hundred-billion-dollar global TAM — hidden in missed GDP, avoidable surgeries, wasted spend. As stigma collapses and capital flows (see Melinda Gates’ $100M push into women’s health research), this space will mint new category leaders.
And unlike overfunded areas where 20 startups chase the same GLP-1 or the same AI scribes, here the greenfield is wide open. The first company to deliver real, scalable relief for women’s chronic pain will not just be a unicorn — it will be a generational company.
The Bottom Line
Endometriosis is not just an unmet need. It’s among the largest overlooked commercial opportunity in healthcare.
The science is catching up. The stigma is breaking. The capital is starting to flow.
For founders: this is your moment to define the wedge. For VCs: this is your chance to be early, not late.
Women’s pain is no longer invisible. The only question is: who’s going to build the next giant by finally taking it seriously?"