Endometriosis is a chronic medical condition where tissue similar to the endometrium (the inner lining of the uterus) grows outside the uterus. These misplaced tissues behave like normal endometrial tissue, they thicken, break down, and bleed during each menstrual cycle. However, with no way to exit the body, they become trapped, leading to inflammation, pain, and scarring [1].
The diagnosis of endometriosis remains a challenge due to its variable symptoms and overlap with other conditions. On average, it takes 7–10 years from symptom onset to diagnosis [2].
Epidemiology and Context
Endometriosis affects approximately 10% of women and people assigned female at birth during their reproductive years, roughly 190 million globally [2]. It is one of the leading causes of pelvic pain and infertility.
Early and accurate diagnosis is essential to managing symptoms, preventing complications, and improving quality of life. Despite its prevalence, the condition is often underdiagnosed or misdiagnosed, commonly mistaken for irritable bowel syndrome (IBS) or pelvic inflammatory disease (PID).
Where Does Endometriosis Occur?
Endometrial-like tissue is most commonly found in the pelvic region. Common anatomical sites include:
- Ovaries (often forming cysts called endometriomas)
- Fallopian tubes
- Outer surface of the uterus
- Pelvic peritoneum (the membrane lining the abdominal wall and covering pelvic organs)
Less frequently, endometriosis can also appear on the bladder, bowel, diaphragm, and in rare cases, the lungs and brain [1].
Key Symptoms and Clinical Signs
Endometriosis can present with a wide range of symptoms. The most frequently reported include:
- Severe pelvic pain (especially during menstruation)
- Dysmenorrhoea (painful periods)
- Dyspareunia (pain during intercourse)
- Dysuria (painful urination) or dyschezia (painful bowel movements), especially during periods
- Chronic lower abdominal or back pain
- Infertility or difficulty conceiving
The severity of symptoms does not always correlate with the extent of the disease. Some individuals with extensive endometriosis have little pain, while others with minimal disease experience severe symptoms.
The Diagnostic Journey
1. Initial Consultation and History Taking
The first step in diagnosis is a detailed medical history. A doctor will ask about:
- Menstrual patterns
- Nature and timing of pelvic pain
- Digestive or urinary symptoms
- Family history of endometriosis
Because symptoms mimic other conditions, a thorough and honest discussion is vital.
2. Physical Examination
A pelvic exam may help identify abnormalities such as cysts or scar tissue. However, this method alone is rarely sufficient, especially in cases of deep or small lesions.
3. Imaging Techniques
Several non-invasive methods are used to support a diagnosis:
- Transvaginal ultrasound (TVUS): This is often the first imaging tool used. It can detect ovarian endometriomas but may not identify superficial or deep lesions.
- Magnetic resonance imaging (MRI): Offers detailed images and may help locate deep infiltrating endometriosis (DIE) affecting ligaments or organs like the bowel or bladder.
Imaging can support clinical suspicion but cannot definitively diagnose all forms of endometriosis.
4. Laparoscopy: The Gold Standard
Laparoscopy is currently the only definitive method to diagnose endometriosis.
This minimally invasive surgical procedure involves inserting a thin camera (laparoscope) through a small incision in the abdomen to view the pelvic organs.
If endometrial-like tissue is found, samples (biopsies) may be taken for histological confirmation (examining tissue under a microscope). This also allows the surgeon to remove visible lesions during the same procedure, if appropriate.
Classification and Staging
Once diagnosed, the severity of endometriosis is commonly staged using the Revised American Society for Reproductive Medicine (rASRM) classification, ranging from Stage I (minimal) to Stage IV (severe). Staging is based on:
- Location and extent of implants
- Presence and severity of adhesions (bands of scar tissue)
- Size of ovarian endometriomas
This staging helps guide treatment but doesn’t always reflect the level of pain or impact on fertility.
Complications and Advanced Presentations
If undiagnosed or untreated, endometriosis can lead to:
- Infertility due to inflammation, scarring, and anatomical distortion
- Endometriomas (ovarian cysts filled with dark fluid)
- Adhesions that can fuse organs together
- Bowel or bladder dysfunction if deeply infiltrating tissue affects these organs
In rare cases, endometriosis has been linked to increased risks of certain cancers, such as ovarian cancer, though this is not common.
Common Misconceptions
A few myths still persist around diagnosis:
- “A normal scan means you don’t have endometriosis” – False. Imaging may miss small or deep lesions.
- “Endometriosis only affects older women” – False. Many are diagnosed in their teens or early 20s.
- “It’s just a bad period” – False. The level of pain and life disruption far exceeds typical menstrual discomfort.
Accurate information helps reduce delays in seeking care.
Diagnostic Recommendations
If you suspect endometriosis:
- Keep a pain diary detailing symptoms, their timing, and severity
- Speak with a gynaecologist experienced in managing endometriosis
- Don’t dismiss persistent pain, early intervention improves long-term outcomes
While laparoscopy remains the definitive tool, advances in imaging and greater awareness are helping reduce delays in diagnosis.
Summary
Endometriosis is a complex, often misunderstood condition with a significant delay in diagnosis. It requires a combination of symptom tracking, physical examination, imaging, and sometimes surgery to confirm. Early diagnosis is key to managing symptoms, preserving fertility, and improving quality of life.
References
[1] Leyland, N. et al., Endometriosis: Diagnosis and Management, NICE Guidelines, 2017. Link
[2] Johnson, N.P. et al., Endometriosis and Fertility: Impact and Management, Human Reproduction Update, 2017. Link
[3] Giudice, L.C., Clinical Practice: Endometriosis, The New England Journal of Medicine, 2010. Link
