INTRODUCTION:The objective of these clinical practice guidelines was to analyse all of the interventions during pregnancy and childbirth that might prevent obstetric anal sphincter injuries (OASIS) and postnatal pelvic floor symptoms.MATERIAL AND METHODS:These guidelines were developed in accordance with the methods prescribed by the French Health Authority (HAS).RESULTS:A prenatal clinical examination of the perineum is recommended for women with a history of Crohn's disease, OASIS, genital mutilation, or perianal lesions (professional consensus). Just after delivery, a perineal examination is recommended to check for OASIS (Grade B); if there is doubt about the diagnosis, a second opinion should be requested (Grade C). In case of OASIS, the injuries (including their severity) and the technique for their repair should be described in detail (Grade C). Perineal massage during pregnancy must be encouraged among women who want it (Grade B). No intervention conducted before the start of the active phase of the second stage of labour has been shown to be effective in reducing the risk of perineal injury. The crowning of the baby's head should be manually controlled and the posterior perineum manually supported to reduce the risk of OASIS (Grade C). The performance of an episiotomy during normal deliveries is not recommended to reduce the risk of OASIS (Grade A). In instrumental deliveries, episiotomy may be indicated to avoid OASIS (Grade C). When an episiotomy is performed, a mediolateral incision is recommended (Grade B). The indication for episiotomy should be explained to the woman, and she should consent before its performance. Advising women to have a caesarean delivery for primary prevention of postnatal urinary or anal incontinence is not recommended (Grade B). During pregnancy and again in the labour room, obstetrics professionals should focus on the woman's expectations and inform her about the modes of delivery.