How to get an endometriosis diagnosis (UK)

Symptoms NICE says to take seriously

NICE NG73 (Endometriosis: diagnosis and management) tells GPs to suspect endometriosis when a woman or person assigned female at birth presents with one or more of:

Chronic pelvic pain.
Period-related pain (dysmenorrhoea) that affects daily activities and quality of life.
Deep pain during or after sex (dyspareunia).
Period-related or cyclical gastrointestinal symptoms, especially painful bowel movements.
Period-related or cyclical urinary symptoms, especially blood in urine or pain passing urine.
Infertility associated with one or more of the above.

The NICE NG73 pathway

NICE recommends:

A focused history and abdominal/pelvic examination — though absence of findings does not rule endometriosis out.
Considering transvaginal ultrasound to look for ovarian endometriomas or signs of deep endometriosis (and where TVUS isn't appropriate, transabdominal).
Referring to a gynaecologist for further assessment and investigation when initial management has not worked or when symptoms are severe.
Referring to a specialist endometriosis service if deep endometriosis involving bowel, bladder or ureter is suspected.

What to bring to your GP

A 12-week pain and bleeding diary: dates, severity 0–10, what stopped you doing, painkillers taken.
Cycle dates and length over those 12 weeks.
Any bowel or bladder symptoms with timing relative to your period.
Impact on work, education, sex, sleep — concrete, not adjectives.

Referral wording

Dear Dr [name], I'm asking for referral to gynaecology under NICE NG73 (Endometriosis: diagnosis and management) for suspected endometriosis. I have [list symptoms from NG73: chronic pelvic pain / cyclical bowel pain / dyspareunia / infertility, etc.] for [duration]. I have kept a [12-week] symptom diary, attached. I understand NICE NG73 states that examination, ultrasound and MRI findings can be normal in endometriosis and that this should not preclude referral. Please refer me to gynaecology. If you don't feel this is clinically appropriate, please document the reason in my notes. Thank you.

Scans and laparoscopy

Transvaginal ultrasound is often the first imaging investigation, looking for endometriomas and signs of deeper disease. MRI is added where deep infiltrating endometriosis is suspected. The definitive diagnosis is laparoscopy with histological confirmation of endometrial-like tissue outside the uterus.

If your GP won't refer, see our guide on refused referrals. A formal, NG73-cited letter is the single most effective lever for a delayed endometriosis referral. Finally Seen writes one for £49.

Frequently asked questions

›What is the only definitive way to diagnose endometriosis?

Laparoscopy with histological confirmation remains the diagnostic gold standard for endometriosis. NICE NG73 says the absence of findings on examination, ultrasound or MRI does not rule out endometriosis — referral should still be considered.

›How long does diagnosis usually take?

Endometriosis UK estimates an average diagnostic delay of 7–9 years from first symptoms. The pathway can be much faster if the GP refers to gynaecology early under NICE NG73.

›Can endometriosis be diagnosed on a scan?

Transvaginal ultrasound and MRI can identify some forms (e.g. ovarian endometriomas, deep infiltrating endometriosis), but a normal scan does not exclude the diagnosis — superficial peritoneal disease can only be confirmed surgically.

›Do I have to try hormonal treatment first?

NICE recommends offering hormonal management for symptoms while investigations are arranged — but it is not a precondition for referral. If your GP is making it one, ask for the clinical reasoning in writing.