The main objective of this study is to compare pelvimetric measurements performed by Magnetic Resonance Imaging (MRI) and by the EOS imaging system.

During pregnancy, after failure of External Manual Version (EMV) in case of breech fetal presentation, a radiological pelvimetry is performed to evaluate the measurements of the pelvis and decide on the appropriate mode of delivery.

Several imaging modalities are used, including pelvic computed tomography (CT),and magnetic resonance imaging (MRI) of the pelvis.

CT scan has the disadvantage of maternal irradiation and MRI has the disadvantage of an inaccurate morphological analysis.The EOS® system is an imaging tool used in radiopediatric to allow precise morphological analysis of bone masses with minimal irradiation.

The quality of the morphological analysis and measurements provided by the EOS® imaging system is the reason for proposing this study comparing the pelvimetric measurements obtained by MRI and by the EOS® imaging system.

Inclusion Criteria:

• Patients > 18 years of age
• Patient requiring pelvimetry (breech fetus)
• Gestation > 36 SA (weeks of amenorrhea)
• Patients with BMI < 35
• Affiliated to social security or similarly regime
• Patients who gave their consent to participate in the study (Patient having agreed to perform both examinations: MRI and EOS system)

Exclusion Criteria:

• Patient with a contraindication to MRI (claustrophobia, pace-maker, intracorporeal metallic element)
• Patient with a contraindication to performing EOS® (person not standing alone)
• Patient who are in exlusion period of another interventiionnal study
• Person deprived of freedom by judicial or administrative decision; person hospitalized for psychitric care; person under legal protection measure.