Endometriosis Risk Assessment

The gold standard remains diagnostic laparoscopy with histological confirmation of endometrial glands and stroma in biopsied lesions. However, NICE (NG73) and ESHRE guidelines now support clinical diagnosis and empirical treatment in women with typical symptoms (cyclical pelvic pain, dysmenorrhoea, dyspareunia) without requiring mandatory laparoscopy before treatment. Laparoscopy is indicated if symptoms do not respond to medical treatment, if there is an adnexal mass, or if the presentation is atypical.

The ENZIAN classification is a surgical staging system designed specifically for deep infiltrating endometriosis (DIE), which is poorly captured by the rASRM system. ENZIAN uses compartments: Compartment A (vagina, recto-vaginal septum), B (uterosacral ligament, parametrium), and C (rectum, sigmoid). Each is graded 1–3 by depth. ENZIAN separately classifies involvement of the adnexa, urinary system, and other organs. It enables precise surgical communication and planning.

CA-125 has poor sensitivity and specificity for endometriosis diagnosis. It is elevated in only 25–30% of women with minimal-mild disease and in 60–80% of those with severe disease. It is also elevated in other conditions including ovarian cancer, other gynaecological conditions, and even menstruation itself. CA-125 cannot be used alone to diagnose or exclude endometriosis, but markedly elevated levels (>200 U/mL) alongside a suspicious USS or MRI raise suspicion for significant disease or malignancy.

Medical treatments include: hormonal suppression (combined oral contraceptive pill, progestogens, Mirena IUS, GnRH agonists/antagonists such as elagolix or relugolix); analgesics (NSAIDs, paracetamol); and add-back HRT during long-term GnRH agonist use to prevent osteoporosis. Surgical treatments include: laparoscopic excision of peritoneal lesions, ovarian cystectomy, and resection of DIE. Surgery for severe or DIE should be performed at specialist centres. Definitive treatment (bilateral salpingo-oophorectomy) is rarely indicated except at menopause.

Endometriosis is associated with a small but real increased risk of ovarian cancer, specifically the endometrioid and clear cell subtypes. The absolute risk is low — women with endometriosis have approximately a 2–3-fold increased lifetime risk compared to women without endometriosis, though the absolute lifetime risk remains below 2%. This association is predominantly seen with ovarian endometrioma rather than peritoneal disease.

Not always. Many women with endometriosis conceive naturally. However, endometriosis is found in 25–50% of women investigated for infertility, and even mild peritoneal disease can reduce monthly fecundity rates (natural conception probability per cycle) from approximately 20–25% to 2–10%. Fertility is more significantly affected by ovarian endometrioma (which can damage follicular reserve), tubal disease, and severe adhesions.

Adenomyosis is a condition in which endometrial glands and stroma are present within the myometrium (uterine muscle), causing a bulky, tender uterus with heavy, painful periods. It is distinct from endometriosis (which is outside the uterus) but both conditions frequently coexist and share some pathophysiological mechanisms. Adenomyosis is diagnosed by TVUS (heterogeneous myometrium with cystic spaces) or MRI (junctional zone thickness >12 mm).

Studies from the UK, US, Australia, and Germany consistently show an average diagnostic delay of 7–10 years from first symptom onset to confirmed diagnosis. Reasons include normalisation of period pain by patients and clinicians, the need for laparoscopy for definitive diagnosis, limited endometriosis knowledge in primary care, and the absence of a reliable non-invasive biomarker. This delay significantly impacts quality of life, fertility, and disease progression.