The purpose of this study was to compare the short-term operative outcomes of three different surgical techniques for uterine incision closure during caesarean section (CS). This trial enrolled 120 patients scheduled for primary caesarean delivery. Patients were randomised into either classical double-layer uterine closure, purse-string double-layer uterine closure (Turan), or our new approach of uterine closure (double layer step up-step down technique). For short-term comparison, transvaginal ultrasonography was planned for all patients 6 weeks after surgery. Compared to group II and Group III, residual myometrial thickness was significantly thinner in group I (p < .001). The number of patients with uterine niche was 10 (50% of all scar defects) in group I whereas it was 4 (20%) in group II and 6 (30%) in group III. Operative time was significantly longer in group II (p < .001). This led to our conclusion that Turan technique and our new approach are associated with thicker myometrial thickness and less frequency of uterine scar defect than classical double-layer uterine incision closure; however, our approach takes less operative time. Clinical Trial Registration: ClinicalTrials.gov Identifier: NCT04681378Impact statementWhat is already known on this subject? Many variations in CS technique have been studied. For example, single-layer uterine incision closure has been compared to double-layer uterine incision closure. Purse string double layer (Turan) has been also compared to the traditional double-layer technique. Double layer unlocked closure has been shown to result in a thicker residual myometrium and as a consequence can possibly lead to the decrease of niche development after a CS compared to single-layer closure with lower frequency of uterine scar defect with Turan technique.What do the results of this study add? Here we introduce a new uterine closure technique, which we have named double-layer step up-step down technique, as an alternative method. With this technique, the uterine incision contract more than with the traditional double layer technique and has similar results to the Turan technique; however, our approach takes less operative time.What are the implications of these findings for clinical practice and/or further research? These alternative techniques of uterine incision closure decrease the frequency of uterine niche that may be associated with many clinical problems such as ectopic pregnancy at the CS scar, placenta accreta, rupture of the uterus during a subsequent pregnancy. Future studies are needed to investigate the frequency of uterine rupture in a subsequent pregnancy following different uterine incision closure techniques.
Keywords: Caesarean section; scar defect; surgical technique; uterine incision closure.