The objective of this review was to evaluate whether interventions performed during labour could influence the risk of perineal tears.
A separate keyword search for each medical intervention during labor was performed by selecting only studies evaluating perineal consequences, particularly the risk of obstetrical anal sphincter injury (LOSA). Interventions during pregnancy and during fetal expulsion have been specifically addressed in other chapters of the recommendations.
Maternal mobilisation and postures during the first stage of labour have not been shown to reduce the risk of OASIS (LE3). No particular posture has demonstrated its superiority over any other during the second stage of labour for preventing obstetric perineal lesions including OASIS and postnatal incontinence (urinary or faecal) (LE2). There is no reason to recommend one maternal posture rather than another during the first and the second stages of labour for the purpose of reducing the risk of OASIS (Grade C). Women should be allowed to choose the position most comfortable for them during the first and second stages of labour (Professional
consensus). Posterior cephalic positions present the greatest risks of perineal injury (LE2). Manual rotation of cephalic posterior positions to the anterior during the second stage of labour may make it possible to reduce the risk of operative vaginal delivery, although no reduction in the risk of perineal injuries or OASIS has been clearly demonstrated (LE3). For fetuses in posterior cephalic positions, no data justifies a preference for manual rotation at full dilation to diminish the risk of perineal injury (Professional
consensus). Urinary catheterisation is recommended for women with epidural analgesia during labour when spontaneous micturition is not possible (Professional
consensus). Although current data does not justify a preference for continuous or intermittent urinary catheterisation (LE2), intermittent catheterisation nonetheless appears preferable in this situation (Professional
consensus). During the second stage phase, delayed pushing does not modify the risk of OASIS (LE1). It does, however, increase the chances of spontaneous delivery (LE1). It is thus recommended that, when maternal and fetal status allow it, the start of pushing should be delayed (Grade A). There is no evidence to support preferring one pushing technique rather than another to diminish the risk of OASIS (grade B). Performing an operative vaginal delivery for the sole purpose of reducing the duration of the second stage of labour may increase the risk of OASIS (LE3). Perineal massage or the application of warm compresses during the second stage of labour appear to reduce the risk of OASIS (LE2). However, we have not made a determination about their use in clinical practice.