Synopsis
Recognise the varied symptom patterns of endometriosis, begin treatment and investigation in parallel, and refer appropriately without allowing normal examination or imaging to end the diagnostic pathway.
- Suspect endometriosis with chronic pelvic pain, dysmenorrhoea affecting activities and quality of life, deep pain during or after sex, cyclical bowel or urinary symptoms, or infertility accompanied by one or more of these features.
- The disease is defined by endometrium-like tissue outside the uterus; symptoms arise from inflammation, fibrosis, adhesions, ovarian endometriomas and deep infiltration, while pain severity correlates poorly with visible extent.
- Take symptoms in adolescents seriously, including school absence and pain resistant to simple treatment; people aged 17 and under with suspected or confirmed disease need a paediatric and adolescent gynaecology or specialist endometriosis service.
- NICE recommends transvaginal ultrasound for everyone with suspected endometriosis even when abdominal and pelvic examinations are normal; use transabdominal ultrasound when transvaginal scanning is declined or unsuitable.
- A normal examination, ultrasound or MRI does not exclude endometriosis, particularly superficial peritoneal disease; continue referral and treatment decisions according to symptoms and impact.
- Do not use serum CA125 to diagnose endometriosis: it lacks the accuracy to confirm or exclude disease and may be raised in several benign or malignant conditions.
- Investigation, referral and initial pharmacological treatment should proceed in parallel; laparoscopic proof is not required before a supported trial of analgesia or hormonal treatment.
- Refer an endometrioma, suspected deep disease involving bowel, bladder or ureter, or disease outside the pelvis to a specialist endometriosis service with imaging, pain, fertility and surgical expertise.
Key red flags
Syncope, haemodynamic change, guarding, rebound tenderness or abrupt maximal pain requires urgent assessment for ectopic pregnancy, torsion, cyst rupture, haemorrhage or another surgical cause.
Cyclical haematuria, flank pain, hydronephrosis or falling renal function may indicate ureteric or urinary-tract endometriosis and needs specialist assessment before irreversible renal damage occurs.
Vomiting, abdominal distension, inability to pass stool or flatus, or severe rectal bleeding suggests bowel obstruction or another gastrointestinal emergency rather than uncomplicated cyclical bowel pain.
Postmenopausal bleeding, a new complex adnexal mass, ascites, weight loss or progressive non-cyclical symptoms must enter the appropriate cancer pathway.
Severe pain with fever, offensive discharge or systemic illness raises pelvic infection, abscess or postoperative complication and requires prompt assessment.
Investigation priorities
Identify endometriomas and deep endometriosis, assess bowel, bladder or ureteric clues, find alternative pathology and guide the referral destination.
Management branches
One or more NICE symptom patterns suggest endometriosis, whether examination is normal or abnormal.
- Record the cycle, bowel, bladder, sexual, functional and fertility pattern and offer a pain and symptom diary if it would help the person communicate changes.
- Offer transvaginal ultrasound, or transabdominal imaging when needed, while beginning appropriate analgesic or hormonal treatment and addressing immediate quality-of-life needs.
- Give clear information that normal imaging cannot exclude disease and set a review point rather than asking the person to return only when symptoms become intolerable.