Endometriosis: Definition and Symptoms

Quick answer

Endometriosis is a chronic gynaecological disease characterised by the presence of tissue similar to the endometrium outside the uterine cavity. This tissue responds to the hormonal variations of the menstrual cycle: it bleeds, becomes inflamed and scars, causing pain and sometimes infertility.

What is endometriosis?

Endometriosis is a chronic gynaecological disease characterised by the presence of tissue similar to the endometrium (the lining of the uterus) outside the uterine cavity. This ectopic tissue responds to the hormonal variations of the menstrual cycle: it bleeds, becomes inflamed and scars, causing progressive lesions and chronic pain.

It affects about 10% of women of childbearing age (2 to 4 million women in France) and is often diagnosed with a delay of 7 to 10 years after the first symptoms.

Type	Location	IR treatment at Cochin
Superficial (peritoneal)	Peritoneum, depth < 5 mm	Surgery (laparoscopy)
Ovarian (endometrioma)	Endometriotic cyst of the ovary	Surgery, possible ultrasound-guided aspiration
Deep infiltrating	Uterosacral torus, rectovaginal septum, bladder	Surgery, cryoablation depending on location
Parietal (scar-related)	Caesarean scar, laparotomy scar	Percutaneous cryoablation (a Cochin speciality)

Symptoms of endometriosis

Dysmenorrhoea (intense menstrual pain, 2nd to 3rd day): the cardinal symptom, often disabling
Chronic pelvic pain between periods
Deep dyspareunia (pain during sexual intercourse)
Infertility: 30-40% of infertile women have endometriosis
Cyclical digestive (dyschezia) or urinary (haematuria) symptoms in deep endometriosis
Cyclical scar pain in parietal endometriosis (caesarean or laparotomy)

Parietal endometriosis: a speciality of Cochin AP-HP
Parietal endometriosis (implants in a caesarean or laparotomy scar) is treated at Cochin by percutaneous cryoablation under CT or MRI guidance. This minimally invasive technique (no incision, local anaesthesia) is an alternative to surgical excision, with excellent results on cyclical pain.

Frequently asked questions

Can endometriosis heal spontaneously?

No. Endometriosis is a chronic disease that does not heal spontaneously during the reproductive years. It may however regress after the menopause. Medical (hormonal) and surgical treatments aim to reduce symptoms and lesions.

How can parietal endometriosis be distinguished from a recurrence at the caesarean scar?

MRI is the reference examination. Parietal endometriosis appears as a tissue nodule in or under the scar, often in contact with the underlying myometrium, with a characteristic signal on T1 and T2. Fine-needle aspiration is possible in case of doubt.

Does cryoablation of parietal endometriosis preserve fertility?

Yes. Cryoablation does not affect the uterine cavity or the ovaries. It does not affect future fertility. A pregnancy is possible in the months following treatment.

Learn more

Cryoablation of endometriosis at Cochin

Technique, procedure and results of percutaneous cryoablation of parietal endometriosis.

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Scientific references

Percutaneous image-guided cryoablation of abdominal wall endometriosis: towards a novel standard of care?

Cornelis FH, Moyne T, Dohan A. Diagn Interv Imaging 2024;105(9):299-300.

Percutaneous cryoablation of abdominal wall endometriosis: a systematic literature review of safety and efficacy

Bodard S, Razakamanantsoa L, Geevarghese R, O'Gorman J, Dohan A, Marcelin C, Cornelis FH. Insights Imaging 2024;15:282.

🇫🇷 French version: endometriose-definition.html

Why this page is trustworthy

Written by the Interventional Radiology team at Cochin Hospital AP-HP, Université Paris Cité. Medically reviewed by an interventional radiologist of the department. Last updated: July 2026.

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Endometriosis: Definition, Types and Symptoms