Is an episiotomy always necessary during an operative vaginal delivery with vacuum? A longitudinal study

Abstract

Objective: The use of episiotomy during operative vaginal birth (OVB) is rather debated among operators and in literature. It is also important to evaluate the indications for which episiotomy is performed. In fact, the consequences of an episiotomy can be invalidating for patients with long-lasting results. The aim of this study is the evaluation of the role of episiotomy during OVB with the vacuum extractor and its correlation with Obstetric Anal Sphincter Injuries (OASIs).

Methods: On of 9165 vaginal births, a total of 498 OVB (5.4%) were enrolled in a longitudinal prospective observational study. The incidence of OASIs was evaluated in our population after OVB performed with the vacuum extractor, during which the execution of episiotomy was performed indicated by clinician in charge.

Results: OASIs occurred in 4% of the patients (n = 20). Episiotomy was performed in 39% of them (n = 181). OASIs incidence was 6% (n = 17) in the No Episiotomy and 1.8% (n = 3) in Episiotomy group (p<.001). Performance of episiotomy during OVB determined a protective effect against OASIs (p = 0.025 in full cohort and p = 0.013 in the primiparous group). An expulsive phase under one hour was an almost significant protective factor (p = 0.052).

Conclusions: The use of episiotomy during OVB was associated with much lower OASIs rates in nulliparous women with a vacuum extraction; OR 0.23 (CI 95% 0.07-0.81) p = 0.037 in nulliparous women and the number necessary to treat was 18 among nulliparous women to prevent 1 OASIs. A further risk factor that emerged from the analysis is a prolonged expulsive period, whereas fundal pressure does not seem to have a statistically significant influence.

Keywords:

• Operative vaginal birth
• obstetric anal sphincter injuries
• OASIs
• episiotomy
• perineal tear

Ethics approval

This study was approved by Institutional Review Board (IRB for clinical trial Tuscany: AREA VASTA NORD OVEST, Stabilimento di Santa Chiara, Pisa, Prot n 60166)

Authors’ contributions

All authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by all authors. AF analyzed and interpreted the patient data. The first draft of the manuscript was written by AR, FF, AS, PM and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.

Data availability statement

The data that support the findings of this study are available from the corresponding author, F.F., upon reasonable request.

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.