Comparison of obstetric anal sphincter injuries in nulliparous women before and after introduction of the EPISCISSORS-60® at two hospitals in the United Kingdom

Abstract

Aim: To assess whether the introduction of episiotomy scissors specially designed to achieve a cutting angle of 60°, EPISCISSORS-60®, in two hospitals in the UK would result in a reduction in obstetric anal sphincter injuries (OASIS) in nulliparous women. Methods: A structured training program for all doctors and midwives provided a theoretical framework around OASIS including risk factors and the role of episiotomies and a practical hands-on training element to use EPISCISSORS-60® correctly and to measure perineal body length and post-suturing angles. Data for perineal body length, post-suturing angles, user feedback, episiotomy use, and incidence of OASIS were collected through specifically designed forms and the general hospital data collection system. Results: Data were available for 838 nulliparous vaginal deliveries. Mean perineal body length was 37 mm in spontaneous vaginal delivery group (standard deviation [SD] =8.3, 95% confidence interval [CI] =34–39) and 38 mm in the operative vaginal delivery group (SD=8, 95% CI=35–40). Post-suturing episiotomy angles were 53° (SD=6.5, 95% CI=50.7–55.8) in spontaneous vaginal deliveries and 52° (SD=9.6, 95% CI=49–54) in operative vaginal deliveries. EPISCISSORS-60® were rated as “good” to “very good” by 84% of users. There was a 47% increase in the number of episiotomies in nulliparous spontaneous vaginal deliveries at Poole (P=0.007) and a 16.5% increase in the number of episiotomies in nulliparous operative vaginal deliveries in Hinchingbrooke (P=0.003). There was an overall 11% increase in episiotomy numbers in nulliparous vaginal deliveries (P=0.08). There was a statistically significant OASIS reduction of 84% in nulliparous spontaneous vaginal deliveries in women who received an episiotomy (P=0.003). Conclusion: Initial results after introduction of EPISCISSORS-60® show that the majority of health care professionals achieve post-suturing episiotomy angles between 40° and 60°. The results also show a significant increase in the use of episiotomies in the delivery of nulliparous women. There has been a statistically significant reduction in OASIS in nulliparous spontaneous vaginal deliveries.