Incomplete healing of the uterine incision after elective second cesarean section

Purpose: To evaluate the possible associations between the single-layer locked- and unlocked-uterine closure technique and closure area biometry, and cesarean scar healing in recurrent cesarean section. Material and methods: In this randomized prospective study, elective second cesarean section of 120 singleton pregnant women were randomized into the single-layer locked- and unlocked-continuous uterus closure technique. During the operation, the upper and lower edge thickness of the uterine incision were measured. In order to evaluate the healing in the cesarean scar area, all women were examined with vaginal ultrasonography 6-8 months after the cesarean section. The possible associations between locked- and unlocked-uterine closure technique and closure area biometry and cesarean scar healing were evaluated. Results: After the drop-outs, a total of 86 women, 45 in the locked-continuous closure group and 41 in the unlocked-continuous closure group were evaluated. There was no statistically significant difference between the groups in terms of demographic and clinical parameters, such as perioperative uterine closure area biometry, need for additional suture, duration of operation and amount of bleeding. However, a significantly greater number of additional sutures for hemostasis was necessary in the unlocked-continuous compared to the locked-continuous closure group. The rate of cesarean scar defect (CSD) and residual myometrium thickness were comparable whereas the healing rate was significantly higher in the locked-continuous closure group compared to the unlocked-continuous closure group (0.71 +/- 0.90 vs. 0.64 +/- 0.10, p = .032). In women with CSD, the lower edge was 4 mm thinner than the women without CSD (10.48 +/- 6.13 mm vs. 14.53 +/- 7.13 mm, p = .006). Moreover, the thickness difference between the lower and upper edge was significantly greater if CSD was present compared to the absence of CSD (5.88 +/- 4.04 mm vs. 3.70 +/- 3.00 mm, p = .006). Conclusions: There was no association between CSD and locked versus unlocked suture technique used for the closure of uterine incision in the second cesarean section. The biometric evaluation of the scar area has shown that the thin lower wound edge and unevenness between the lower and the upper wound edges may play a role in incomplete healing of the uterine incision.