Suture type for hysterotomy closure: a systematic review and meta-analysis of randomized controlled trials

Objective: Recent randomized controlled trials have demonstrated an association between uterine closure technique at the time of cesarean delivery and short- and long-term operative outcomes with varied results. This systematic review and meta-analysis aimed to examine types of suture material used for cesarean delivery. Data sources: Scopus, PubMed, Cochrane Central Register of Controlled Trials, Ovid, and ClinicalTrials.gov were searched from inception of each database to October 2021. Study eligibility criteria: All randomized controlled trials that compared types of suture materials used for hysterotomy closure during low-transverse cesarean delivery at ≥24 weeks' gestation and examined maternal outcomes were included for this review. The primary outcome was estimated blood loss. Secondary outcomes included additional surgical complications. Methods: Results were summarized as mean difference or risk ratio with associated 95% confidence intervals. The quality of studies was evaluated with the Cochrane Handbook for Systematic Reviews of Interventions for judging risk of bias. Heterogeneity was measured using I-squared (Higgins I2). Results: This review included 7 randomized controlled trials, of which 3 compared multifilament with barbed suture (136 vs 136 participants), 3 compared multifilament with conventional monofilament suture (245 vs 244 participants), and 1 trial compared multifilament with chromic suture (4590 vs 4595 participants). Primary analysis showed no difference in estimated blood loss between the multifilament and the barbed suture group (mean difference, 46.2 mL; 95% confidence interval, -13.6 to 105.9), nor in change in hemoglobin concentration between the multifilament and the conventional monofilament group (mean difference, -0.1%; 95% confidence interval, -0.5 to 0.3). Secondary outcomes showed a reduction in operative time with barbed vs multifilament suture (mean difference, 1.9 minutes; 95% confidence interval, 0.03-3.8). Analysis also demonstrated an increased uterine scar thickness with use of conventional monofilament vs multifilament suture (mean difference, -1.05 mm; 95% confidence interval, -1.9 to -0.2). Conclusion: This meta-analysis does not support a specific type of suture material for uterine closure at cesarean delivery because of insufficient data. Although barbed suture was associated with an overall decrease in operative time, and use of conventional monofilament suture was associated with an increase in uterine scar thickness, the clinical utility of these differences is not clear. Further adequate randomized controlled trials are warranted for evaluation of different suture materials for hysterotomy closure. Keywords: barbed suture; cesarean deliery; hysterotomy; monofilament; multifilament; pregnancy; suture material; suture technique; uterine closure; uterus