Antibiotic Prophylaxis for Prevention of Postpartum Perineal Wound Complications : A Randomized Controlled Trial

The anal sphincter is vulnerable during vaginal delivery, more so during forceps than during vacuum deliveries. Breakdown of a repair frequently is associated with infection at the repair site. Breakdown of a third-degree perineal repair (extending into the capsule and muscle of the anal sphincter) or a fourth-degree repair (extending through the sphincter into the rectal mucosa) may lead to incontinence of stool or flatus, sexual dysfunction, or formation of a rectovaginal fistula. This prospective, randomized, placebo-controlled trial was designed to show whether antibiotics given at the time of repair diminish the rate of perineal wound infection and breakdown. The study population included 147 women aged 18 and older who had sustained a third- or fourth-degree perineal tear at the time of vaginal delivery. Sixty-four patients received a single intravenous dose of a second-generation cephalosporin, either cefotetan or cefoxitin, at the time of repair, whereas 83 received a placebo. The perineum was inspected at the time of discharge and again 2 weeks after delivery. The primary end-point was gross disruption or purulent discharge at the site of repair. Just over one-fourth of women failed to return at 2 weeks. Of those who did return, 8.2% of antibiotic-treated patients and 24.1 % of placebo recipients had a perineal wound complication (P = .037). Purulent discharge from the perineal wound was significantly less frequent in the treated group (4% versus 17%, P = .036). Women in the treated and control groups did not differ with respect to parity, the incidence of diabetes, operative delivery rates, or the presence of a third- or fourth-degree perineal tear. The investigators believe that administering a prophylactic antibiotic when repairing a third- or fourth-degree perineal laceration lessens the risk of wound complications.