Endometriosis: why diagnosis still takes years — and what the latest research says

What endometriosis actually is

Endometriosis is a condition in which tissue similar to the lining of the uterus grows outside the uterus — on the ovaries, fallopian tubes, the outer surface of the uterus, the bowel, the bladder, and in some cases on organs as distant as the diaphragm and lungs. This tissue responds to hormonal cycles the same way the uterine lining does: it thickens, breaks down, and bleeds. But unlike the uterine lining, it has nowhere to go.

The result is inflammation, scar tissue, adhesions, and — for most people with the condition — significant pain. The pain is not limited to menstruation. It can be present throughout the cycle, during sex, during bowel movements, during urination, and as a chronic background presence that shapes every aspect of daily life.

A 2023 systematic review and meta-analysis by Becker and colleagues, published in Human Reproduction Open, confirmed that endometriosis affects approximately 10% of reproductive-age women globally — roughly 190 million individuals. The authors noted that despite this prevalence, the condition remains consistently underfunded and undertreated relative to other chronic diseases of comparable burden.

The condition is far more common in specific clinical contexts. Among women who seek care for pelvic pain, prevalence rises to approximately 34%. Among those experiencing infertility, 25 to 30% have endometriosis. These figures make clear that endometriosis is not a rare edge case — it is a condition that a significant proportion of women presenting with pain or fertility concerns are living with, often without a name for it.

Endometriosis is also associated with fatigue, bloating, nausea, and — in approximately 25 to 50% of cases — infertility. It is a systemic condition, not a localized one.

Why it still takes years to diagnose

The diagnostic delay in endometriosis is not a mystery. It is the predictable outcome of several converging factors, each of which reflects a broader pattern in how women's pain is heard, investigated, and taken seriously.

A 2024 analysis of U.S. insurance claims data, published in the Journal of Women's Health, found that endometriosis diagnosis rates rose 32% between 2017 and 2024, reaching approximately 33 per 10,000 patients. The highest rates were in women aged 35 to 49, at roughly 85 per 10,000 — a figure that reflects both peak prevalence and the reality that many women are not diagnosed until their mid-thirties or later, despite having had symptoms since adolescence. A rising diagnosis rate is progress. It is also an indictment: it means that for decades, these women were symptomatic and undiagnosed.

First: pain normalization. Women with endometriosis typically begin experiencing symptoms at the onset of menstruation. They are told, repeatedly, that painful periods are normal. That everyone has them. That they should take ibuprofen and get on with it. A 2022 systematic review by Hirsch and colleagues, published in BJOG, analyzed diagnostic delay data across 16 countries and confirmed that the average delay from symptom onset to diagnosis ranges from 5 to 12 years — with delays longest in countries where primary care providers have the least endometriosis-specific training.

Second: symptom overlap. Endometriosis symptoms — pelvic pain, bowel symptoms, bladder symptoms, fatigue — overlap with irritable bowel syndrome, interstitial cystitis, pelvic inflammatory disease, and other conditions. The result is a well-documented pattern of misdiagnosis: women with endometriosis routinely receive multiple incorrect diagnoses — IBS, anxiety, pelvic inflammatory disease — before anyone considers endometriosis. Each wrong turn adds months or years to the delay.

Third: the diagnostic barrier. Definitive diagnosis of endometriosis has historically required laparoscopic surgery. A 2022 ESHRE guideline update acknowledged that while high-resolution transvaginal ultrasound and MRI can detect deep infiltrating endometriosis and ovarian endometriomas in experienced hands, they cannot reliably exclude superficial peritoneal disease — meaning surgical visualization remains the gold standard for a complete diagnosis. This barrier means that getting diagnosed still requires a provider willing to refer for investigation, and many are not.

Fourth: research underfunding. Endometriosis affects roughly the same number of people as diabetes. A 2020 analysis in PLOS ONE found that endometriosis receives substantially less research funding per patient than conditions of comparable prevalence and burden — a gap that directly limits progress on non-invasive diagnostics, targeted therapies, and understanding of disease mechanisms.

The cost of waiting — in numbers

Years of undiagnosed endometriosis is not a neutral experience. It is years of pain that has been normalized, dismissed, or attributed to other causes. It is missed work, cancelled plans, and relationships strained by a condition that no one has named.

The economic cost is substantial. A 2023 analysis by Soliman and colleagues, published in the Journal of Managed Care and Specialty Pharmacy, estimated the total annual direct and indirect cost of endometriosis in the United States at over $78 billion — a figure that includes healthcare utilization, surgical costs, and lost workplace productivity. Women with endometriosis were found to incur significantly higher annual healthcare costs than matched controls without the condition.

The quality-of-life impact is equally documented. A 2022 multinational study published in the American Journal of Obstetrics and Gynecology found that women with endometriosis reported significantly lower scores across all health-related quality-of-life domains — physical functioning, pain, emotional wellbeing, and social functioning — compared to population norms, with scores in ranges comparable to those seen in people with rheumatoid arthritis and inflammatory bowel disease.

The psychological cost is harder to quantify but no less real. A 2021 meta-analysis published in Human Reproduction found that women with endometriosis have significantly elevated rates of depression and anxiety compared to the general population — a finding that is not surprising when you consider what years of unacknowledged pain does to a person's relationship with their own body and with the healthcare system.

Treatment: what exists and what's missing

There is no cure for endometriosis. Current treatments manage symptoms and slow progression; they do not eliminate the condition.

Hormonal therapies — combined oral contraceptives, progestins, GnRH agonists and antagonists — suppress the hormonal cycling that drives endometriosis growth and can significantly reduce pain for many people. The 2022 ESHRE endometriosis guideline recommends hormonal treatment as first-line medical management, noting that GnRH antagonists (including the newer oral options relugolix and elagolix) offer additional flexibility compared to older injectable GnRH agonists.

Excision surgery — performed by a specialist in endometriosis — removes endometriosis lesions from the pelvic cavity. A 2021 Cochrane systematic review confirmed that laparoscopic surgery reduces endometriosis-associated pain compared to diagnostic laparoscopy alone, and that complete excision of visible disease is associated with better outcomes than ablation for deeply infiltrating lesions. Access to excision specialists remains limited; waitlists are long; insurance coverage is inconsistent.

Pain management — including NSAIDs, nerve blocks, and pelvic floor physical therapy — addresses symptoms without affecting the underlying condition. It is an important part of comprehensive care but is not a substitute for diagnosis and disease management.

What is missing, for most people with endometriosis, is a coordinated care team that treats the condition as the complex, systemic disease it is — rather than a series of individual symptoms to be managed in isolation.

How to push for a faster diagnosis

The diagnostic delay in endometriosis is not inevitable. People who are informed, who name the condition explicitly, and who push for referral to a specialist are diagnosed faster. This should not be the patient's job — but until the system changes, it is.

If you have been experiencing pelvic pain, painful periods, pain during sex, bowel or bladder symptoms, or unexplained fatigue — and if these symptoms have been dismissed or attributed to other causes — endometriosis is worth raising explicitly with a provider.

Ask for a referral to a gynecologist who specializes in endometriosis. Ask what the criteria are for considering laparoscopy. Ask what other conditions are being ruled out and on what timeline. You are allowed to push for answers on a condition that has been affecting your life for years.