Incidence of obstetric anal sphincter injuries after implementing the Triep-45 tool to improve episiotomy angle in instrumental deliveries

Objective To assess the impact of Triepi-45-a tool that enables an episiotomy angle of 45 degrees to be marked on the perineum at rest-on the incidence of obstetric anal sphincter injuries (OASIS) during operative vaginal delivery (OVD). Method A retrospective-prospective cohort study was performed among successive women who underwent OVD at Complejo Asistencial Universitario de de Leon, Spain, between 2011 and 2013 (preintervention cohort, n=986) and between 2014 and 2016 (intervention cohort, n=986) after implementation of an interventional programme in 2013 to improve the episiotomy angle, including use of Triepi-45, in OVD. Results The intervention cohort had a lower incidence of OASIS than the preintervention cohort (70/986 [7.1%] vs 93/986 [9.4%]), but the difference was not significant, owing to the low use of Triepi-45 in the intervention cohort (n=375). However, the OASIS incidence was significantly lower in the Triepi-45 cohort than in the preintervention cohort (18/375 [4.8%] vs 93/986 [9.4%]; odds ratio, 0.47; 95% confidence interval, 0.26-0.86). Conclusion Use of Triepi-45 had a positive impact on reducing OASIS in OVD. It remains essential to raise obstetricians' awareness of the importance of the episiotomy angle and to implement the systematic use of tools to reduce the incidence of OASIS.