Objective To explore the clinical characteristics, treatment methods, and prognostic risk factors of cesarean scar endometriosis (CSE), and to provide evidence for standardized management.

Methods A retrospective analysis was conducted on the clinical data of patients with postoperatively pathologically confirmed CSE who underwent primary surgical treatment at the Obstetrics and Gynecology Hospital of Fudan University from January 1, 2015, to June 30, 2024. According to the deepest tissue involved as determined during intraoperative exploration, patients were classified into three types: typeⅠ(fascia type), typeⅡ(anterior sheath muscle type), and type Ⅲ (peritoneal type). Differences in general patient characteristics among the subtypes were compared, and recurrence was followed up.

Results A total of 321 patients were included, with age of (31.82±3.82) years. 95.6% patients had Pfannenstiel incision. The latent period was (34.45±26.43) months, patients younger than 35 years (P＝0.005), with lactation duration less than 6 months (P＜0.001), and with maximum lesion diameter less than 4 cm (P＝0.011) had shorter latent periods. Typical symptoms of cyclical pain with mass enlargement at the scar site were present in 84.4% of patients. Preoperative ultrasound and magnetic resonance imaging (MRI) both had a positive predictive value of 100% for CSE, but MRI was superior to ultrasound in accuracy rate of assessing lesion infiltration depth (96.9% vs 50.5%) and measuring lesion size. Patients with type Ⅲ lesions had the highest proportion with maximum lesion diameter ＞3 cm (52.8%) and requiring mesh repair (25.0%). The follow-up period was (21.3±12.6) months, and the recurrence rate was 1.82%. Younger age (P＝0.030) and multiple lesions (P＝0.048) were influencing factors for postoperative recurrence.

Conclusions The latent period of CSE is correlated with age, lactation duration and lesion size. Younger patients and those with multiple lesions have a higher risk of recurrence.