Pelvic MRI in gynaecology: when it is used, what happens, limitations

What is a pelvic MRI?

Magnetic resonance imaging (MRI) uses a magnetic field and radio waves to produce detailed images of soft tissues. It does not use X-rays. In the pelvis, it shows the uterus and its different layers, the ovaries, the vagina, the bladder, the rectum and the ligaments connecting them.

In gynaecology, MRI is almost always a second-line test, after a clinical examination and a pelvic ultrasound. It answers a specific question: clarifying an abnormality, mapping before surgery, or assessing how far a disease has spread. It thus helps choose the treatment and, if an operation is needed, plan it (see Gynaecological surgery).

When is a pelvic MRI needed in gynaecology?

The main indications endorsed by medical societies are as follows.

For endometriosis, the European Society of Urogenital Radiology (ESUR) updated its recommendations in 2025: a standardised protocol, a report organised by pelvic compartment, and a classification of lesions to make communication between radiologist, surgeon and patient easier.

Ovarian cyst: what does the O-RADS MRI score mean?

About a quarter of ovarian masses seen on ultrasound remain indeterminate: it cannot be said with certainty that they are benign. The O-RADS MRI score grades these masses from 1 to 5 according to their risk of cancer. In a multicentre study in 15 European centres involving 1,130 women, this score had a sensitivity of 93% and a specificity of 91%; no invasive cancer was graded as score 2.

In practice, a low score often allows simple monitoring or conservative surgery, while a high score points towards a team specialising in gynaecological cancer. MRI is the second-line test for masses that ultrasound cannot classify. To find out more: benign ovarian cysts.

How do I prepare for a pelvic MRI?

• Tell the centre about any metal object or device: pacemaker, defibrillator, nerve stimulator, cochlear implant, metal fragments, old surgical clips, pump. Some are contraindications; others require a compatibility check. A copper coil (IUD) is generally compatible, but it must be mentioned.
• Mention a possible pregnancy, any allergy, kidney failure or claustrophobia. A gadolinium-based contrast agent is often injected; it is avoided during pregnancy unless necessary.
• Fasting: depending on the centre's protocol, you are often asked not to eat for a few hours to limit bowel movement.
• Bladder: a moderately full bladder is usually requested; follow the centre's instructions.
• Specific preparation for endometriosis: ESUR recommends fasting, a medicine that slows the bowel, a moderately full bladder and sometimes rectal preparation (enema or gel). The imaging centre will give you the details.
• Timing in your cycle: not usually required, unless your doctor asks for it.
• Bring the referral, your previous ultrasound and MRI scans, and your latest creatinine results if you were asked for them.

What happens during a pelvic MRI?

You remove any metal objects and lie on your back on a table that slides into a tunnel open at both ends. A coil (antenna) is placed over your pelvis. The scanner is noisy: headphones or earplugs are provided. You stay in contact with the radiographer through a microphone and a call button.

It is important to keep still and follow the breathing instructions. Depending on the protocol, contrast agent is injected into a vein in your arm during the scan, and sometimes a gel is placed in the vagina or rectum to show certain areas better. The duration depends on the protocol; the imaging centre will tell you how long to expect. You can return to your usual activities straight afterwards.

What are the limitations of pelvic MRI?

• It is not a first-line test: ultrasound, more accessible and accurate in many situations, remains the first test.
• MRI does not provide a microscopic diagnosis: only a biopsy or analysis of tissue removed at surgery confirms the nature of a lesion.
• A normal MRI does not rule out all endometriosis: superficial lesions on the peritoneum are hard to see.
• Interpretation depends on the radiologist's experience, hence the value of centres experienced in women's imaging and of standardised reports.
• Practical constraints: contraindications linked to some devices, claustrophobia, sometimes long waiting times.

How do I read my MRI report and what happens next?

The radiologist writes a report describing each organ, measuring any lesions and, where relevant, grading them with a standardised score (for example O-RADS for an ovarian mass, or a compartment-based classification for endometriosis). A conclusion summarises the key findings.

The report is technical: it only makes full sense alongside your symptoms, the clinical examination and the ultrasound. That is the purpose of the results consultation, which can be booked via Doctolib or by calling 01 43 79 59 79. Depending on the findings, several next steps are possible:

• no significant abnormality: no further tests, or simple monitoring;
• benign lesion (endometrioma, fibroid, adenomyosis): medical treatment or monitoring, with surgery only if symptoms justify it;
• indeterminate or suspicious lesion: further tests, review at a multidisciplinary team meeting and care by a specialist team;
• planning an operation: the MRI serves as a map for the surgeon and helps explain to you the likely duration and risks of the operation.

Keep your images and reports: they will be used for comparison at future scans.

Are there any risks or warning signs after a pelvic MRI?

MRI does not involve X-rays and has no known risk under normal conditions of use. Reactions to the contrast agent are rare and usually mild (nausea, flushing). Very rarely, a severe allergic reaction can occur, generally during the scan or shortly afterwards, while the team is monitoring you.

Once you are home, if you notice swelling of the face or throat, difficulty breathing or feel faint, call 15 or 112 immediately in France, or your local emergency number.

Frequently asked questions

General information article: it does not replace a medical consultation. In an emergency, call 15 or 112 in France, or your local emergency number.