I want to open with something a patient said to me that I have never forgotten. She was 34, had been experiencing severe pelvic pain since she was 17, and had just received a diagnosis of stage 3 endometriosis. When I explained what the diagnosis meant, and what treatment options existed, she was quiet for a long moment. Then she said: "So there was a name for it all along."
She had spent 17 years being told her pain was normal. That her periods were just bad. That she was sensitive. Multiple GP appointments. A gynaecology referral that resulted in a normal pelvic ultrasound and discharge. An A&E visit during which a doctor documented dysmenorrhoea and sent her home with ibuprofen.
Seventeen years. And she was not unusual.
The average time from onset of symptoms to diagnosis of endometriosis in the UK is 7.5-8 years. That figure has barely changed in a generation despite endometriosis being well-described in medical literature since the 1920s. For Black and African women, the delay is often longer - the result of symptoms being more readily dismissed, less aggressive investigation, and a persistent clinical myth (now thoroughly refuted) that endometriosis was less common in Black women.
The myth that endometriosis is rare in Black women
For decades, a clinical myth persisted that endometriosis was predominantly a condition of white women, and specifically of professional women who delayed childbearing. This myth was used - implicitly and explicitly - to justify not investigating Black women's pelvic pain with the same urgency.
The evidence does not support this myth. Large studies in the US and UK consistently show that endometriosis prevalence is comparable across ethnicities. What differs is who gets investigated, who gets believed, and who receives timely diagnosis.
This matters clinically because diagnostic delay in endometriosis is associated with disease progression (mild endometriosis can progress to more severe disease), greater cumulative pain and suffering, greater fertility consequences, and greater requirement for more complex surgical intervention.
Symptoms
Endometriosis is characterised by its relationship to the menstrual cycle, though symptoms can be present throughout the month in established disease.
Dysmenorrhoea (painful periods): The most common symptom. Pain that begins 1-2 days before the period, peaks during the heaviest flow, and is significantly worse than standard period cramps. Often requires strong analgesia. Can cause vomiting, fainting, or inability to attend work or school. This level of dysmenorrhoea is not normal - it warrants investigation.
Chronic pelvic pain: Persistent pelvic pain throughout the month, not limited to menstruation. Often worse in the second half of the menstrual cycle. Can become constant in severe disease.
Deep dyspareunia: Pain during or after penetrative sex - specifically deep pain, not superficial. Caused by endometriosis deposits in the pouch of Douglas or on the uterosacral ligaments. Women often find this too embarrassing to volunteer; doctors often do not ask.
Dyschezia: Painful bowel movements, particularly around menstruation. Caused by endometriosis involving the bowel.
Dysuria: Painful urination or urinary urgency, particularly around menstruation. Caused by bladder endometriosis.
Fatigue: Profound fatigue that is disproportionate to activity levels. Partly from chronic pain, partly from the inflammatory state endometriosis creates.
Fertility: Endometriosis is found in 25-50% of women investigated for infertility. Mechanisms include anatomical distortion from adhesions, effects on egg quality, effects on the uterine environment, and effects on tubal function. The relationship between minimal and mild endometriosis and fertility is less clear.
The diagnostic problem - why ultrasound is often not enough
A transvaginal ultrasound is normal in the majority of women with endometriosis. This is the single most important clinical point that leads to women being told there is nothing wrong.
Standard ultrasound identifies ovarian endometriomas (endometriosis cysts on the ovaries) and large deposits but misses peritoneal, deep infiltrating, and small superficial endometriosis deposits - the most common forms.
A normal ultrasound does not exclude endometriosis. It is not evidence that endometriosis is absent. It is evidence that endometriosis was not visible on that imaging modality.
Specialist transvaginal ultrasound performed by a sonographer trained specifically in endometriosis mapping has much higher sensitivity for deep endometriosis. MRI with endometriosis-specific protocol similarly has high sensitivity for deep infiltrating disease.
Definitive diagnosis requires laparoscopy (keyhole surgery) with direct visualisation and biopsy of suspected endometriosis deposits. This is the gold standard.
Case study: Nadia's decade of dismissal
Nadia, 35, came to see me having recently moved to London from Accra. She had seen three gynaecologists in Ghana, each of whom had performed a pelvic ultrasound, found nothing, and reassured her that her periods were simply painful and that this was something some women had to manage.
Her pain score during periods was consistently 9-10/10. She took ibuprofen 2,400mg per day during the first three days of every cycle and it barely touched the pain. She had stopped planning anything for the first week of every month. She described having lost relationships because of the unpredictability of her pain.
I referred her directly to a BSGE-accredited endometriosis centre rather than back through general gynaecology.
An MRI with endometriosis protocol revealed deep infiltrating endometriosis of the uterosacral ligaments and rectovaginal septum. Laparoscopy confirmed stage 3 endometriosis with extensive adhesions and endometriomas on both ovaries.
She underwent excision surgery with a specialist endometriosis surgeon. Eight weeks after surgery, her most recent period: pain score 3/10, managed with standard ibuprofen.
"I lost my twenties to this," she told me. "Every doctor just did an ultrasound and said nothing was there."
Treatment options
Hormonal management: The combined oral contraceptive pill, progestogen-only methods, GnRH agonists (leuprorelin, goserelin), and the newer relugolix combination (Ryeqo) all manage endometriosis by suppressing the hormonal cycle that drives it. They manage symptoms effectively but do not remove the disease. Symptoms typically return when hormones are stopped.
Ablation surgery: Burning or destroying endometriosis deposits with heat or laser energy. High recurrence rates - the roots of the disease are often not fully treated by surface destruction.
Excision surgery: Cutting out endometriosis deposits completely, including their roots, from the surrounding tissue. The gold standard surgical treatment with significantly better long-term outcomes and lower recurrence rates than ablation. Requires specialist surgical training and is performed at BSGE-accredited centres.
For women with significant endometriosis, excision surgery performed by a specialist is worth the wait and the additional referral steps.
Sources: NICE Clinical Guideline NG73 - Endometriosis (2017, updated 2023); Endometriosis UK - Endometriosis Facts and Figures 2023; Moradi M et al, Journal of Endometriosis 2014; Missmer SA et al, Human Reproduction 2004 (endometriosis epidemiology); Yeung P et al, Journal of Minimally Invasive Gynecology 2011 (excision vs ablation); BSGE Accredited Centres list 2024.
