Evaluation of a policy of restrictive episiotomy on the incidence of perineal tears among women with spontaneous vaginal delivery: A ten-year retrospective study

Abstract

Introduction: Routine episiotomy is no longer recommended to limit obstetrical anal sphincter injuries (OASIs). We aimed to evaluate the effect of a restrictive policy of episiotomy on the risk of OASIs during spontaneous vaginal deliveries.

Material and methods: We performed a retrospective single-center observational study among women with a term singleton cephalic fetus, with spontaneous vaginal delivery. The occurrence of episiotomy, intact perineum, first, second, third or fourth-degree (OASIs) perineal tears were compared before (period A, from 01/01/2006 to 12/31/2008) and after (period B, from 01/01/2012 to 12/31/2016) implementation of the restrictive policy. Odds of perineal tear were estimated using multivariable logistic regression models, stratified by parity.

Results: From 2006-2016, the rate of episiotomy decreased, from 14.9 % (n/N=200/1141) to 4.7 % (94/1912). In period B (N=8984) vs A (N=8984), the rates of episiotomy were, 12.9 vs 26.6 % for nulliparas (p<0.01) and 2.3 vs 6.8 % for multiparas (p<0.01). Odds of OASIs were not different in period B vs A, both for nulliparas (0.9 vs 0.8 %, AOR=0.88(0.38-2.05)) and multiparas (0.4 vs 0.2 %, AOR=2.28(0.63-8.29). Odds of second-degree tear were higher in period B vs A, both for nulliparas (39.8 vs 17.4 %, AOR=2.55(2.11-3.08) and multiparas (26.2 vs 12.8 %, AOR=2.26(1.95-2.66)); and odds of intact perineum were lower (for nulliparas, 15.8 vs 24.9 %, AOR=0.61(0.42-0.90) and for multiparas, 47.1 vs 56.0 %, AOR=0.61(0.49-0.76)). No difference was observed for first-degree tears.

Conclusion: The progressive implementation of a restrictive policy of episiotomy during spontaneous vaginal delivery was not associated with an increased risk of OASIs over a ten-year period.

Keywords: Episiotomy; OASIs; Perineal tear; Spontaneous vaginal delivery.