Morbidity associated with episiotomy in vacuum delivery: a systematic review and meta-analysis.

Background: The role of episiotomy in vacuum deliveries is controversial.

Objectives: To perform a meta-analysis of the literature examining this subject.

Search Strategy: The search was conducted in four databases.

Selection Criteria: Two investigators independently selected original research examining the effects of episiotomy on any neonatal and maternal outcomes during vacuum delivery.

Data Collection And Analysis: The effect estimates were presented as odds ratios (ORs) with 95% confidence intervals (95% CIs).

Main Results: Fifteen articles were included, encompassing a total of 350 764 vacuum deliveries. A non-significant relationship was shown between mediolateral episiotomy and obstetric anal sphincter injuries (OASIS) in nulliparous women (OR 0.68, 95% CI 0.43-1.07; six studies), whereas an increased risk was demonstrated in parous women (OR 1.27, 95% CI 1.05-1.53; two reports). A higher risk of OASIS with median episiotomy use was shown in nulliparous (OR 5.11, 95% CI 3.23-8.08; two studies) as well as in parous (OR 89.4, 95% CI 11.8-677.1; one study) women. Lateral episiotomy was related to lower OASIS risk in nullipara (OR 0.59, 95% CI 0.49-0.70; single paper). Mediolateral episiotomy was linked to increased rates of postpartum haemorrhage (OR 1.82, 95% CI 1.16-2.86) and analgesia use (OR 2.10, 95% CI 1.39-3.17; two reports). Overall, the quality of evidence was rated as low to very low.

Author's Conclusions: Mediolateral and median episiotomy in parous woman may increase the rate of OASIS at vacuum delivery, whereas lateral episiotomy in nulliparous women could be associated with a decreased risk of OASIS. The suboptimal quality of the available evidence necessitates high-quality well-designed randomised trials.

Tweetable Abstract: Episiotomy in vacuum delivery does not appear to be of benefit, and might even increase maternal morbidity.