A Randomized Controlled Trial in a Teaching Hospital Comparing the Outcomes of Single-Layer versus Double-Layer Uterine Suturing with Polyglactin in the Development of Uterine Niche Following Caesarean Section

Background Caesarean section (CS) rates are rising globally, with Egypt reporting one of the highest rates. A potential complication of CS is the development of a uterine scar defect, or niche, which may be associated with abnormal bleeding, dysmenorrhea, and infertility. The technique of uterine closure may play a significant role in the prevention of niche formation. Aim To evaluate the effectiveness of double-layer uterine closure versus single-layer closure in preventing niche formation after a first CS, as assessed by transvaginal ultrasound (TVUS) at six weeks postpartum. Methods This randomized controlled trial was conducted at Mataryia Teaching Hospital, Cairo, including 174 women undergoing their first CS. Participants were randomly assigned to single-layer (n=87) or double-layer (n=87) uterine closure using polyglactin sutures. Baseline maternal and intraoperative characteristics were documented. Outcomes included prevalence of niche, large niche, residual myometrial thickness (RMT), adjacent myometrial thickness (AMT), abnormal bleeding, and dysmenorrhea. Statistical analysis included chi-square tests and multivariable logistic regression. Results Baseline characteristics were comparable between groups. Niche formation was observed in 28.7% of the single-layer group and 25.3% of the double-layer group (p=0.609). Large niches were significantly more frequent in the double-layer group (9.2% vs. 1.1%, p=0.017). No significant differences were noted regarding abnormal bleeding (11.5% vs. 9.2%, p=0.619) or dysmenorrhea (6.9% vs. 8.0%, p=0.773). Multivariable logistic regression did not identify closure technique as a significant predictor of niche formation. Conclusion Double-layer closure did not reduce the overall prevalence of niche compared to single-layer closure. Unexpectedly, large niches were more frequent in the doublelayer group. These findings suggest that uterine closure technique may influence niche characteristics, but further studies are warranted.