Wound complications after obstetric anal sphincter injuries

The aim of this study was to estimate the incidence of and risk factors for wound complications in women who sustain obstetric anal sphincter injuries. Five hundred two women met inclusion criteria for the study, and, finally, 268 women (54%) were enrolled. Eighty-seven percent of the cohort was nulliparous and 81% had a third-degree laceration. The majority (n=194) underwent an operative vaginal delivery (66.0% forceps and 6.0% vacuum). The overall risk was 19.8% (95% confidence interval [CI] 15.2-25.1%) for wound infection (n=53) and 24.6% (95% CI 19.6-30.2%) for wound breakdown (n=66). Operative vaginal delivery was related to wound complications (infection, breakdown, or both) (adjusted odds ratio [OR] 2.54, 95% CI 1.32-4.87, P=.008). Intrapartum antibiotic therapy for obstetric indications was associated with a decreased risk of wound complications (adjusted OR 0.50, 95% CI 0.27-0.94, P=.03). Women with a wound complication reported significantly greater pain within 1 week of delivery than women with a normally healing perineum (visual analog scale: 40.1±25.6 compared with 31.0±23, P=.002); this persisted at 12 weeks postpartum (6.6±7.5 compared with 3.4±7.1, P=.005).

The study found that women who sustain obstetric anal sphincter injuries are at a greater risk of developing wound complications in the early postpartum period, calling for immediate and consistent follow-up.