Background: Interest in the possible long-term morbidity of CS scars has increased because to the rising CS rate. Hysteroscopic niche resection is the least intrusive surgical procedure. Only a small number of studies have documented hysteroscopic resections thus far. There have been no documented problems, and success rates in reducing postmenstrual spotting that are high. Objective: This study aimed to compare women who experienced postmenstrual spotting to control patients who received no intervention, the efficacy of a hysteroscopic resection of a post-cesarean scar defect (CSD) (niche). Patients and methods:  This was a randomized controlled trial that had been performed in Early Cancer Detection and Gynecological Endoscopy Unit in Ain Shams University Maternity Hospital, and in Menoufia University Hospital, during the period from May 2020 to February 2022. Results: There was highly significant difference between both groups regarding their clinical improvement in the form of absence of postmenstrual spotting after first menstrual cycle of randomization, 77.8% of cases improved after one month of operation, the percentage increased to 88.9% in the second month of follow up. Only one patient (3.7%) still had minimal spotting after three months of operation and randomization. There was significant relation between postoperative improvement and niche depth postoperatively among the study group. Improved cases had significantly smaller niche depth than the non-improved cases with niche depth less than 6.5 mm as shown by ROC curve (P value 0.005). Conclusion: Hysteroscopic resection of CSD (niche) was a safe and successful procedure, particularly in women with residual myometrial thickness (RMT) more than 4 mm.