How is endometriosis diagnosed?

Endometriosis diagnosis usually starts with a doctor listening to your symptoms and examining you, followed in most cases by imaging such as ultrasound or MRI. Normal imaging does not rule out endometriosis. In that case, or when medication does not work, a doctor may consider laparoscopy (a small keyhole operation with a camera). Only a doctor can make the diagnosis.

What are the steps on the diagnostic path?

1. History and symptoms. You will be asked when the pain started, how it relates to your period, whether sex is painful, about bowel and urinary symptoms and any wish to get pregnant. The NICE guideline notes that keeping a symptom and pain diary can be useful.
2. Examination. An abdominal and, where appropriate, vaginal examination. According to ESHRE the diagnostic accuracy of examination is low, so imaging should be considered even if the examination is normal.
3. Imaging. ESHRE recommends using ultrasound or MRI in the diagnostic work-up. The guideline also stresses that a negative result does not rule out endometriosis, particularly superficial disease.
4. Trial of medication. ESHRE states that imaging combined with a trial of hormone treatment (the contraceptive pill or a progestogen), or diagnostic laparoscopy, can be considered; neither has been shown to be better, and the pros and cons should be discussed with a doctor.
5. Laparoscopy. Considered if imaging is negative, or if a trial of treatment was unsuccessful or not appropriate. Testing a tissue sample (biopsy) is recommended, although a negative result does not entirely rule out the disease.

Which method does what?

Method	What it is for	What to know
History and examination	Raising suspicion, referral	Cannot diagnose alone; accuracy is low
Ultrasound	Ovarian cysts (endometrioma) and deep disease	A negative result does not rule out endometriosis
MRI	Extent of deep disease	A negative result does not rule out endometriosis
Laparoscopy	Seeing the lesions and treating at the same time if needed	A surgical procedure that needs anaesthesia

The ESHRE guideline also recommends not using biomarker measurements in endometrial tissue, blood, menstrual or uterine fluids to diagnose endometriosis.

Why does diagnosis take years?

The 2022 ESHRE guideline reports an average of 8 to 12 years between the first symptoms and a reliable diagnosis. For young people the wait can be longer: in a study reported in the guideline, people whose symptoms began in adolescence waited three times as long as those whose symptoms began in adulthood, and more often reported not being taken seriously or being told nothing was wrong.

Things that contribute to the delay:

• Pain being treated as “normal”. The World Health Organization notes that many people and many health workers do not know that severe pelvic pain is not normal, leading to normalisation and stigma.
• Symptoms resembling other conditions.
• Imaging sometimes looking normal.
• The definitive method being surgical.

Read more in our article on why diagnosis comes late.

New, non-surgical methods

Both ESHRE and WHO say reliable diagnostic methods that do not need surgery are needed, and list research in this area as a priority. This research is ongoing; today’s guidelines do not recommend an established non-surgical diagnostic test.

Prepare for your appointment

The symptom checklist helps you prepare a summary to take to your appointment. For more on what to look out for, see the symptoms page.