Minimizing tearing during vaginal delivery with a perineal protection device: a randomized controlled trial

There is a growing body of evidence indicating that second-degree tears cause both short- and long-term consequences. Very few preventative measures have been found to reduce the incidence of these tears.

This study aimed to investigate whether the use of a perineal protection device during vaginal birth reduces severe perineal tearing (grade ≥2 tear) in primiparous women compared with routine manual perineal support.

A single-center randomized controlled trial was conducted in Sweden from 2019 to 2021. Primiparous women at term were randomly allocated to the intervention group (n=43), where a perineal protection device was used, or to the routine care group (n=49). The primary outcome was grade of perineal tear. The secondary outcomes were vaginal and labial tearing. Continuous data were analyzed using the Student t test or Mann-Whitney U test. Dichotomous data were analyzed using the Pearson X² test, Fisher exact test, and ordinal logistic regression.

Women in the intervention group had a significantly lower risk of sustaining more extensive perineal tearing than those in the control group. The use of the perineal protection device decreased the risk of grade ≥2 tears in relation to grade 0 to 1 tears (odds ratio, 0.40; 95% confidence interval, 0.17-0.94). Ordinal logistic regression analyses revealed an odds ratio of 0.36 (95% confidence interval, 0.16-0.81) per incremetn of grade injury using the perineal protection device vs routine care (P=.013). The number needed to treat using the perineal protection device was 4.3 to avoid 1 grade ≥2 tear. Women in the treatment group showed less labial tearing (P=.016). No adverse effect was detected.

The use of a perineal protection device reduced the risk of grade ≥2 perineal tearing by 60% and labial tearing. El resumen está disponible en Español al final del artículo.