[Management of third and fourth degree perineal tears: A systematic review]

This was a comprehensive literature review using Pubmed, Medline, Embase and Cochrane, whose aim was to analyse the prevalence of anal sphincter injuries, their risk factors, their management and their functional prognosis. The prevalence of 3rd and 4th degree perineal tears varies between studies from 2.95% regardless the parity to 25% in nulliparous women. Twenty-eight percent to 48% of these lacerations were clinically occult. Perineal tears were associated with (multivariate analysis) forceps (6.021 [IC 95% 1.23-19.45]), nulliparity (OR 9.8 [IC 95% 3.6-26.2]), gestational age over 42 SA (OR 2.5 [IC 95% 1-6.2]), fundal pressure (OR 4.6 [IC 95% 2.3-7.9]), midline episiotomy (OR 5.5 [IC 95% 1.4-18.7]) or fetal weight in interval of 250g (OR 1.3 [IC 95% 1.1-1.6]). There was no difference between the sphincter repair techniques. Post-partum laxative use showed less painful bowel motion and earlier postnatal discharge. Data concerning rehabilitation were contradictory. The rate of anal incontinence 6 months after vaginal delivery were 3.6% following third degree of perineal tear and 30.8% in case of fourth degree of perineal tear. Thirty years after anal sphincter disruption, the prevalence of fecal incontinence reached 6.9%.

[Anal incontinence and obstetrical anal sphincter injuries, epidemiology and prevention]

Our main objectives were to identify risk factors, methods for early diagnosis, and prevention of obstetric anal sphincter injuries (OASIs), using a literature review. The main risk factors for OASIs are nulliparity, instrumental delivery, posterior presentation, median episiotomy, prolonged second phase of labor and fetal macrosomia. Asian origin, short ano-vulvar distance, ligamentous hyperlaxity, lack of expulsion control, non-visualization of the perineum or maneuvers for shoulder dystocia also appear to be risk factors. There is a risk of under-diagnosis of OASIs in the labor ward. Experience of the accoucheur is a protective factor. Secondary prevention is based on the training of birth professionals in recognition and repair of OASIs. Primary prevention of OASIs is based on training in the maneuvers of the second phase of labor; if possible, instrumental extractions should be avoided. Mediolateral episiotomy may have a preventive role in high-risk OASIs deliveries. A robust predictive model is still lacking to allow a selective use of episiotomy.

[Predictive factors of 2-month postpartum anal incontinence among patients with an obstetrical anal sphincter injury]

OBJECTIVES

To determine prevalence of short-term postpartum anal incontinence after obstetrical anal sphincter injury and prognostic factors.

MATERIALS AND METHODS

Retrospective study including every patient with an obstetrical anal sphincter injury between January 2006 and December 2012 in one tertiary maternity unit. Patients were interviewed and examined at 2-month postpartum. Anal incontinence was defined by the presence of at least one of the following symptoms: flatus incontinence, faecal incontinence and faecal urgency.

RESULTS

Among 17,110 patients who delivered vaginally during period study, 134 (0.8%) presented an anal sphincter injury. Postpartum obstetrical data were available for 110 of them. Among those patients, 50 women (45.5%) had at least one symptom of anal incontinence at 2-month postpartum and 8 (7.3%) had faecal incontinence. Only maternal age and second stage duration were significantly associated with anal incontinence after obstetrical anal sphincter injury. The degree of sphincter damage at delivery (IIIa, b, c, IV) was not associated with the risk of anal incontinence at 2-month postpartum.

CONCLUSION

Maternal age and second stage duration were the only risk factor for anal incontinence after obstetrical anal sphincter injury in this study. High prevalence of anal incontinence at 2-month postpartum of obstetrical anal sphincter injury is observed no matter what is the degree of anal sphincter damage. Our results highlight the importance to diagnose all obstetrical anal sphincter injuries whatever the degree of damage.