Residual Myometrial Thickness and Scar Elastography After Single- Versus Double-Layer Uterine Closure Following Primary Cesarean Delivery: A Prospective Cohort Study.

OBJECTIVES

To compare residual myometrial thickness and cesarean scar elastography findings following single- versus double-layer uterine closure in women undergoing primary cesarean delivery.

METHODS

In this prospective comparative cohort study, 100 women undergoing primary cesarean delivery at Izmir City Hospital between November 2024 and February 2025 were included. Participants were allocated according to the operating surgeon's routine uterine closure technique into single-layer (n = 50) and double-layer (n = 50) groups. Maternal characteristics, perioperative outcomes, hemoglobin changes, postoperative pain scores, and the requirement for additional hemostatic sutures were recorded. At 6 weeks postpartum, residual myometrial thickness, endometrial thickness, and cesarean scar elastography were assessed by ultrasonography. Exploratory receiver operating characteristic (ROC) analysis was performed to evaluate the discriminatory performance of the imaging parameters.

RESULTS

Baseline demographic and perioperative characteristics were comparable between groups. The single-layer group required more additional intraoperative hemostatic sutures than the double-layer group (p = .002). Perioperative hemoglobin decline, postoperative pain scores, operative duration, and hospital stay did not differ significantly (all p > .05). Residual myometrial thickness (5.7 versus 4.9 mm, p = .001), endometrial thickness (7.9 versus 6.4 mm, p = .042), and elastography scores (11.1 versus 8.2, p < .001) were significantly greater following double-layer closure. Elastography demonstrated the highest discriminatory performance in the exploratory ROC analysis (AUC = 0.827).

CONCLUSION

Double-layer uterine closure was associated with greater residual myometrial thickness, higher cesarean scar elastography scores, and a reduced need for additional hemostatic sutures than single-layer closure. These findings indicate more favorable early postoperative scar characteristics; however, their clinical significance and implications for long-term reproductive and obstetric outcomes remain uncertain.