Study objective <p>The aim of this study was to assess the impact of endometriosis surgery in the retrocervical area and/or USL on the thickness of the posterior uterine isthmus, and subsequently the potential risk of posterior uterine rupture during labor.</p> Design <p>Retrospective observational study.</p> Setting <p>Improving the management of patients with deep infiltrating endometriosis, keeping in mind potential obstetric consequences.</p> Patients <p>All endometriosis patients treated surgically at the Croix-Rousse University Hospital during the study period for the resection of a lesion on one or both USL and/or in the retrocervical region were included if preoperative and postoperative MRI images were available in their medical record.</p> Interventions <p>Evaluating the variation of posterior uterine isthmus thickness on MRI images after retrocervical surgery for deep infiltrating endometriosis. Searching for predictive markers of posterior uterine isthmus thinning.</p> Measurements and mean results <p>Forty-two patients were included between 2016 and 2020. We observed a significant decrease in the sagittal thickness of the median posterior uterine isthmus after surgery (-2.25&#xa0;mm, 95% CI -3.18 to -1.32, <i>p</i>&lt;.01). A significant association was also found between the thinning of the median posterior uterine isthmus on the sagittal section and preoperative urinary symptoms (<i>p</i> =.04), a history of digestive resection with ileostomy (<i>p</i> =.02) and the presence of post-voiding residue ≥ 100&#xa0;cc postoperatively (<i>p</i>&lt;.01). We observed 6 pregnancies in 4 patients (9.5%). Four pregnancies were carried to term with cesarean delivery.</p> Conclusion <p>The resection of retrocervical endometriosis is associated with postoperative thinning of the posterior uterine isthmus, which seems positively associated with the complexity of the rest of the surgery.</p>