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

Background

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.
Objective

To investigate if the use of a perineal protection device during vaginal birth reduces severe perineal tearing (≥grade 2 tear) in primiparous women compared to routine manual perineal support.
Study design

A single center randomized controlled trial was performed in Sweden 2019-2021. Primiparous women at term were randomly allocated to the intervention group (n=43) where a perineal protection device was used, or to receive routine care (n=49). Main outcome measurement was grade of perineal tear. Secondary outcomes were vaginal and labial tearing. Continuous data was analyzed with Student's T-test or Mann-Whitney U-test. Dichotomous data were analyzed with Pearson X2 test, Fisher's Exact test, and ordinal logistic regression.
Results

Women in the intervention group had a significantly lower risk of sustaining more extensive perineal tearing as compared to the control group. Use of the perineal protection device decreased risk of ≥grade 2 tears, in relation to grade 0-1 tears (OR 0.40 [95% CI 0.17–0.94]). Ordinal logistic regression analyses revealed an OR of 0.36 (0.16–0.81) for one-grade-injury increment, using the perineal protection device vs control group (p=0.013). Number needed to treat using the perineal protection device was 4.3 to avoid one ≥grade 2 tear. Women in the treatment group had less labial tearing (p=0.016). No adverse effects were detected.
Conclusions

Use of the perineal protection device reduced the risk of perineal tearing ≥grade 2 tear by 60% as well as labial tearing.