Local and systemic methotrexate in management of caesarean scar pregnancy

Study Objective: The aim is to analyze the management of cesarean scar pregnancy (CSP) based on local and systemic Methotrexate, a protocol implemented in a referral center. Design: This is an observational, retrospective, monocentric, cohort study with a description of the local protocol, treatment results and tolerance profile. Design Classification III. Setting: Tertiary Referral center. Patients: All patients with CSP, confirmed by a reference ultrasound, without severity criteria requiring emergency surgery, between March 2015 to August 2022 were consecutively included. Interventions: All patients were treated by an Echo-guided trans-vaginal aspiration of the gestational sac followed by a local injection of Methotrexate 1 mg/kg under general anesthesia combined with Mifepristone and followed by an injection of 1 mg/kg within 2 days. Measurement and main finding: We included 35 patients with a mean hCG level of 28 872 UI/l +/- 38 063 UI/l and a mean gestational age of 6.8 +/- 1.6 weeks of gestation. All patients were managed effectively with a good reduction in hCG serum levels. The mean duration of hCG negativation was 66 +/- 38 days after the start of management. Only one patient who had received the department's Methotrexate protocol required a second line of treatment. Among major complications, 2 patients experienced hemorrhagic shock which resolved without recourse to hemostasis hysterectomy. The success rate defined by the absence of recourse to secondary treatment was therefore 91.4 %. Among minor complications, the main complication was methotrexate-induced hepatic cytolysis in 7 patients (20 %). Nine women (26 %) required secondary hysteroscopic resection of trophoblastic retention. Twenty-one patients (60 %) had an ultrasound diagnosis of caesarean scar defect (CSD) after CSP management. Conclusion: The combination of transvaginal ultrasound-guided local MTX, Mifepristone and systemic MTX appears to be an effective treatment protocol for patients with CSP.