3RD-DEGREE OBSTETRIC PERINEAL TEARS - RISK-FACTORS AND THE PREVENTIVEROLE OF MEDIOLATERAL EPISIOTOMY

Objective To determine risk factors for third degree obstetric perinea l tears and to give recommendations for prevention. Design Retrospecti ve case-control study. Setting A teaching hospital in The Netherlands. Participants and methods One hundred and twenty cases of vaginal deli very complicated by third degree perineal tear and 702 uncomplicated v aginal deliveries were compared, with respect to possible risk factors . Results In a multivariate model high birthweight, forceps delivery, induced labour, epidural anaesthesia and parity were risk factors for anal sphincter tear. In addition, mediolateral episiotomy was associat ed with fewer sphincter injuries. Separate analysis of nulli- and mult iparous women demonstrated that high birthweight and epidural anaesthe sia (increased risk) and mediolateral episiotomy (decreased risk) were factors associated with anal sphincter tear only in nulliparous women . Conclusions We found several risk factors for anal sphincter tear. N ulliparous women are at higher risk than multiparous women. Mediolater al episiotomy may be sphincter-saving especially in nulliparous women and therefore prevent them from chronic faecal incontinence.